Unless otherwise noted, information contained in each edition of the Kansas School Naturalist reflects the knowledge of the subject as of the original date of publication.

KSN - Vol 42, No 1 - Muscle NamesVolume 42, Number 1 - January 1996

Muscle Names

by David Saunders


ISSN: 0022-877X






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Publication and mailing of this issue Kansas School Naturalist partly underwritten by contributions from readers like you.

Credits: Line illustrations from this issue are taken from several works by Andreas Vesalius, professor of anatomy at Padua, Italy in the mid-1500's, and from Gray's Anatomy, 1858. For additional background on both the history of anatomy and the origin of bone names underlying the muscles, see the Vol. 38, No. 1, 1992 issue of the Kansas School Naturalist, "Bone Names" by Edward Rowe.

EDITORIAL NOTE: The so-called "technical" language presented here is not just for physicians, but for everyday citizens who will be patients, who will sit on juries judging medical practices, who will vote on health-related laws, and who individually monitor their own health and collectively determine our health insurance rates. The precise use of words is the natural and necessary consequence of being an educated person and is part and parcel of operating as a healthy educated person. Dr. Saunders' essay weaves these terms into everyday life.


Dr. David Saunders is an Assistant Professor of Biology at Emporia State University. He is involved in the teaching of human anatomy and physiology and the bioscientific terminology course.

Muscle Names

by David Saunders

There are over 600 muscles in the human body. Identifying these six hundred muscles is a daunting task. Furthermore, the names of these muscles seem foreign to most of us. Most of our modern anatomical terms were developed throughout the mid- to late-1500s when many anatomists were performing dissections of the human body. (The history of anatomy and dissection is more fully discussed in The Kansas School Naturalist, Vol. 38, No. 1.) As a result of the influence of the early Greek and Roman anatomists, muscles were named using Latin and Greek roots. Thus, if you have some appreciation for Latin or Greek roots, you would have an advantage in knowing the function and/or location of a muscle in the body as a result of its name.


Muscles can be named according to the direction their fibers run, their size, where they are found in the body, what bones they attach to, what the muscle looks like, where it is in relation to certain bones, and their function within the body. Often the name of a muscle contains combinations of each of the above.

1. Direction of Muscle Fibers:
When looking at a muscle, you can often see that it appears to have lines running within it. These lines are composed of muscle fibers and the direction that these fibers run in relation to the midline of the body has been used to provide partial names to many different muscles.

If the fibers of the muscle are running with or parallel to the midline of the body, the term rectus is often used to describe that muscle. Rectus is of Latin origin and literally means "straight." Some examples of muscles that have the term rectus in their name include the rectus femoris and rectus abdominis.

If the fibers of the muscle run at an angle to the midline of the body, they are said to run obliquely. The term oblique is also of Latin origin. Some examples of muscles that have the term oblique associated with their name include the internal and external oblique muscles of the thorax.

2. Muscle Size:
Early anatomists often included the name of the muscle something about its size or length. If a muscle were long, its name would likely include the term longus, while if the muscle were short, its name would contain the term brevis (Latin for "short"). Muscles that were large would have the term maximus (Latin for "largest" or "greatest"), major (Latin for "larger"), or vastus (Latin for "huge") in their names, while small muscles would contain terms such as minimus (Latin for "least" or "smallest") or minor (Latin for "smaller").

3. Location in the Body
Another component of many muscle names is the association of the muscle with a particular area of the body. The rectus abdominis is a straight muscle located in the abdominal region. The palmaris longus is a long muscle that attaches to connective tissue in the palm of the hand. Below are more examples of the Greek and Latin terms for the various regions of the body.

oris (L: "mouth")
oculi (L: "eye")
palmaris (L: "palm of the hand")
abdominis (L: "abdomen")
brachii (G: "arm")
femoris (L: "thigh")
tibialis (L: "shin bone")
peroneus (G: "fibula")
digitorum (L: "finger or toe")
pollicis (L: "thumb")
hallicus (L: "great toe")
costals (L: "rib")
carpi (G: "wrist")
spinalis (L: "spine")
scapularis (L: "shoulder blade")

Where in the body would you expect to find the following: biceps brachii, rectus femoris, adductor pollicis longus, orbicularis oculi, external intercostals, tibialis anterior, spinalis thoracis, peroneus longus?

4. Location of the Muscle Attachment (Association with Bone)
Many muscles are named as a result of their association with a particular bone. The temporalis muscle is found covering the temporal bone while the frontalis muscle is found covering the frontal bone of the skull.

5. Location of Muscle's Origin and Insertion on Bones:
All muscles have an origin and insertion. The origin is the part of the body, usually a bone, where the muscle attaches, and does not move when the muscle contracts. The insertion is the part of the body where the muscle attaches, and moves when the muscle contracts. Some muscles are named based upon their origin and insertion. The first part of the muscle name indicates the origin while the second part indicates the insertion. For example, the muscle that has its origin on the breast bone and clavicle (collar bone) and that inserts on a breast shaped process of the skull is termed the sternocleidomastoid: sterno (G: "breast bone"), cleido (G: "clavicle"), and mastoid (G: "breast shape").

6. Number of Origins:
Some muscles have multiple origins. As a result, the number of origins is often used in the muscle's name. Some common names: the biceps brachii and triceps brachii. The term bi is of Latin origin and refers to "two" while ceps, also of Latin origin, refers to "head." Thus this muscle has two heads that attach to two different origins. How many heads and origins would thetriceps brachii have?

7. Relation of the Muscle to the Bone:
Not only is a muscle sometimes named because of the bone to which it attaches, but the name may be even more detailed to describe where its position is in relation to the bone or body part. Below are given some Latin terms and prefixes that describe position.

supra (L: above or over)
infra (L: below or beneath)
sub (L: below or under)
lateralis (L: the side)
medialis (L: the middle)
inter (L: between or among)
external (L: outer)
internal (L: inner)
superior (L: above or over)
inferior (L: underneath)
dorsi (L: the back)
anterior (L: in front of)

Examples of muscles that contain some of the above terms include: supraspinatus, infraspinatus, subscapularis, vastus lateralis, vastus medialis, intercostals, external and internal obliques, superior and inferior rectus muscles of the eye.

Figure 1

Figure 1. Fifth Muscle Tabula from Epitome by Vesalius, 1542.

8. Shape of the Muscle:
Early anatomists often named muscles based upon their resemblance to common shapes. Some muscles named in this fashion include the deltoid, trapezius, orbicularis, and teres.

deltoid (delt, G: "triangle"; oid, G: "like")
trapezius (trapez, G: "table")
serratus (serrat, L: "a saw" or "saw toothed")
teres (tere, L: "round")
orbicularis (orbi, L: circle; cul, L: "little")
latissimus (lat, L: "broad" or "wide"; simus, L: "a likeness")

What would the following muscles look like and where would they be found: latissimus dorsi, orbicularis oculi, orbicularis oris?

9. Type of Action Produced By the Muscle:
The name of many muscles also includes that type of movement (action) which they bring about. Following are some terms that describe movements at joints brought about by muscle contraction. Each of these actions assumes that the body is in the anatomical position.

flexion (flex, L: "to bend") decreases the angle at a joint
extension (ex, L: "out"; ten, L: "stretch") increases the angle at a joint
adduction (ad, L: "to" or "toward"; duct, L: "lead") pulls the limb toward the midline
abduction (ab, L: "away" or "from"; duct, L: "lead") pulls the limb away from the midline
pronation (pron, L: "bent forward") turning the palm downward
supination (supin, L: "lying on the back") turning the palm upward

Muscles that pull an appendage inward are often termed flexors (e.g. flexor carpi radialis, flexor carpi ulnaris) while muscles that bring about extension are termed extensors (e.g. extensor digitorum, extensor carpi radialis).

Figure 2Figure 2. Muscle of the ventral surface of the upper arm from Gray, 1858.


The upper limb (or arm) consists or three distinct regions: the shoulder, the upper arm (brachium) and the forearm (antibrachium).

1. Shoulder

There are six primary muscles of the shoulder:

a. deltoid

  • What would this muscle look like?
  • originates on the scapula and clavicle; inserts on the humerus
  • elevates the arm (abducts) at the shoulder

b. supraspinatus (supra, L: "above", "over", or "beyond"; spina, L: "spine")
c. infraspinatus (infra, L: "below"; spina, L: "spine")
d. subscapularis (sub, L: "below"; scapul, L: "shoulder blade")
e. teres minor (teres, L: "round"; minor, L: "small")
f. teres major (teres, L: "round"; major, L: "larger")

The supraspinatus, infraspinatus, subscapularis, and teres minor are the muscles of the rotator cuff. These muscles are involved in throwing and help to stabilize the humerus (upper arm) in the socket of the shoulder. It is the supraspinatus that is most often damaged in baseball players.

2. Upper Arm Muscles

g. biceps brachii (bi, L: "two"; ceps, L: "head") (brachi, L: "upper arm")

  •  origin on the scapula and humerus; insertion on the radius
  • flexes the upper arm at the shoulder joint
  •  flexes the lower arm at the elbow joint
  • rotates the arm as in turning a screwdriver

h. brachialis (brachi, L: "upper arm"; alis, L: "pertaining to")

  •  origin on the humerus; insertion of the ulna
  • flexes the lower arm at the elbow joint

i. triceps brachii (tri, L: "three"; ceps, L: "head"; brachi, L: "upper arm")

  • origin on the scapula and humerus; insertion on the ulna
  •  extends the arm at the elbow joint
  • known as the "boxer's muscle" as it allows for a straight jab

3. Forearm Muscles

j. brachioradialis (brachi, L: "upper arm"; radialis, L: "radius of the arm")

  •  obtains its name from its origin on the upper arm and its insertion on the radius
  • flexes the forearm at the elbow

k. pronator teres (pron, L: "bent forward"; tor, L: "muscle"; teres, L: "round")

  • originates from the humerus and ulna; inserts on the radius
  • this muscle receives its name due to its action
  • turns the forearm so that the palm faces downward (pronation)

l. flexor carpi radialis (flex, L: "to bend"; carpi, G: "wrist"; radialis, L: "radius")

  • obtains its name from its action, and its origin and insertion
  • originates on the medial portion of the humerus; inserts on the metacarpals
  • flexes and abducts the wrist (moves the wrist away from the midline)

m. flexor carpi ulnaris (flex, L: "to bend"; carpi, L: "wrist"; ulnaris, L: "refers to the ulna")

  • how did this muscle receive its name?
  • originates on the medial portion of the humerus and on the ulna; inserts on the lateral metacarpal
  • flexes and adducts the wrist (moves the wrist toward the midline)

n. palmaris longus (palm, L: "palm of the hand"; longus, L: "long")

  • named as a result of the part of the body it inserts with and the shape of the muscle
  • originates on the medial portion of the humerus; inserts on the connective tissue of the palm
  • flexes the wrist and palm

o. flexor digitorum superficialis (flex, L: "to bend"; digit, L: "finger or toe"; superficialis, L: "above")

  • named for its action on the fingers and its location in relation to other muscles that flex the fingers
  • originates on the humerus; inserts on second digit
  • flexes the wrist and specifically the second finger

p. flexor pollicis longus (flex, L: "to bend"; pollic, L: "thumb"; longus, L: "long")

  • named for its action on the thumb and that is the longest of the muscles that flex the thumb
  • originates on the radius; inserts on the distal bone of the thumb
  • flexes the thumb

q. extensor carpi radialis longus (ex, L: "out or beyond"; tens, L: "to stretch"; carpi, G: "wrist"; radialis, L: "radius"; longus, L: "long")

  • named for its action, the bone with which it is associated, the part of the body that is affected, and the size of the muscle
  • originates on the lateral side of the humerus; inserts on the second metacarpal
  • extends and abducts the wrist

r. extensor carpi ulnaris (ex, L: "out or beyond"; tens, L: "to stretch") (carpi, G: "wrist"; ulnaris, L: ulna)

  • name describes the action of the muscle, the bone that it is associated with, and the part of the body that is affected when the muscle contracts
  • originates on the lateral side of the humerus; inserts on the base of the second metacarpal
  • extends and adducts the wrist

s. extensor digitorum (ex, L: "out or beyond"; tens, L: "to stretch"; digit, L: "finger or toe")

  • name describes the action and parts of the body affected by that action
  • originates on the lateral side of the humerus; inserts on the back of the fingers
  • extends the fingers and the wrist

t. supinator (supin, L: "lying on back"; tor, L: "muscle")

  • name suggests its function
  • originates on the lateral side of the humerus; inserts on the lateral side of the radius
  • turns the arm such that the palm faces upward

Figure 3Figure 3. Second Muscle Tabula from Fabrica by Vesalius, 1543.


Muscle of the Upper Leg

u. Gluteus maximus (glut, G: "the rump"; maximus, L: "largest")

* The gluteus maximus is the largest muscle in the body in regard to mass.

v. gluteus medius (glut, G: "the rump"; medius, L: "middle")

* The gluteus medius is a common site for intramuscular injections

w. gluteus minimus (glut, G: "the rump"; minimus, L: "smallest")

x. rectus femoris (rectus, L: "straight"; femoris, L: "thigh")

Figure 4

Figure 4. Muscle of the ventral surface of the leg from Gray, 1858.

y. vastus lateralis (vastus, L: "huge"; lateralis, L: "the side")

z. vastus medialis (vastus, L: "huge"; medialis, "middle")

aa. vastus intermedius (vastus, L: "huge"; inter, L: "among"; medius, L: "middle")

* The rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius collectively make up the quadriceps muscle (quadr, L: "four"; cep, L: "head").

bb. biceps femoris (bi, L: "two"; ceps L: "head"; femoris, L: "thigh")


cc. semitendinosus (semi, L: "half"; tendin, L: "tendon")

dd. semimembranosus (semi, L: "half"; membran, L: "a membrane")

* The biceps femoris, semitendinosus, and semimembranosus make up the hamstrings. The hamstrings are so named because butchers use the tendons of the muscles to hang "hams" to be smoked.

ee. adductor magnus (ad, L: "to or toward"; duct, L: "lead"; magnus, L: "great or large")

* Damage or tearing of theadductor magnus muscle is often referred to as a "pulled groin muscle".

ff. gracilis (gracil, L: "slender")

gg. sartorius (sartori, L: "a tailor")

* The sartorius is the longest muscle in the human body.

During Vesalius' time, most dissections were performed on animals due to the difficulty of getting human cadavers. Most dissection cadavers were obtained by grave robbing or from criminals that had been hanged. Figure 5 apparently was drawn from the cadaver of a criminal as noted by the noose still associated with the drawing.

Figure 5

Figure 5. Seventh Muscle Tabula from Fabrica by Vesalius, 1543. Note the diaphragm is shown in the upper right hand corner.

hh. gastrocnemius (gastro, G: "belly"; cnem, G: "the part between knee and ankle")

* The gastrocnemius is also called the toe dancer's muscle as it is needed to contract in order for one to stand on his/her toes.

ii. peroneus longus (peron, G: "fibula"; longus, L: "long")

jj. tibialis anterior (tibialis, L: "shin bone") (anterior, L: "in front of")

kk. flexor hallucis longus (flex, L: " to bend"; hallucis, L: "great toe"; longus, L: "long")


ll. pectoralis major (pectoral, L: "breast"; major, L: "larger")

mm. pectoralis minor (pectoral, L: "breast"; minor, L: "smaller")

nn. latissimus dorsi (lati, L: "broad or wide"; dorsi, L: "the back")

oo. trapezius (trapez, G: "a table")

Figure 6

Figure 6. First Muscle Tabula from Fabrica by Vesalius, 1543.

pp. serratus anterior (serrat, L: "a saw"; anterior, L: "in front of")

qq. diaphragm (dia, G: "across"; phragm, G: "a partition")

rr. external intercostals (extern, L: "outer"; inter, L: "between"; costal, L: "rib")

ss. internal intercostals (intern: L: inner; inter, L: "between"; costal, L: "rib")

tt. external oblique (extern, L: "outer"; oblique, L: "angling away from the midline")

uu. internal oblique (intern, L: "inner"; oblique, L: "angling away from the midline")

vv. rectus abdominis (rectus, L: "straight"; abdominis, L: "refers to abdomen")

Figure 7

Figure 7. Ninth Muscle Tabula from Fabrica by Vesalius, 1543.


abdominis (L: "abdomen")
abduction (ab, L: "away or from"; duct, L: "lead")
adduction (ad, L: "to or toward"; duct, L: "lead")
biceps (bi, L: "two"; ceps, L: "head")
brachii (G: "arm")
brevis (L: "short")
carpi (G: "wrist")
costals (L: "rib")
deltoid (delt, G: "triangle"; oid, G: "like")
digitorum (L: "finger or toe")
dorsalis (L: "the back ")
extension (ex, L: "out"; tens, L: "stretch")
external (L: "outer")
femoris (L: "thigh")
flexion (L: "to bend")
gluteus (G: "the rump ")
hallucis (L: "great toe")
internal (L: "inner")
lateralis (L: "the side")
latissimus (lat, L: "broad or wide")
longus (L: "long")
major (L: "larger")
maximus (L: "largest")
medialis (L: "toward the middle")
minimus (L: "smallest")
minor (L: "smaller")
oblique (L: "running at an angle from the midline")
oculi (L: "eye")
orbicularis (orb, L: "circle"; cul, L: "little")
oris (L: "mouth")
palmaris (L: "palm of the hand")
pectoralis (L: "breast")
peroneus (G: "fibula")
pollicis (L: "thumb")
pronation (pron, L: "bent forward")
rectus (L: "straight")
scapularis (L: "shoulder blade")
serratus (L: "a saw ")
sub (L: "under or below")
supination (L: "lying on the back")
supra (L: "above or over")
teres (L: "round")
tibialis (L: "shin bone ")
trapezius (G: "table")
triceps (tri, L: "three"; cep, L: "head")
vastus (L: "huge")
ventralis (L: "underside or belly")
scapularis (L: "shoulder blade")


Ayers, Donald. 1972. Bioscientific Terminology: Words from Latin and Greek Stems. University of Arizona Press: Tucson, AZ.

Borror, Donald J. 1960. Dictionary of Word Roots and Combining Forms. Mayfield Publishing Company: Palo Alto, CA.

Gray, H. 1977. Anatomy, Descriptive and Surgical, A Revised American. From the Fifteenth English Edition. T.P. Pick and R. Howden Eds. Bounty Books: New York, NY.

Martini, F.H. 1995. Fundamentals of Anatomy and Physiology. 3rd Edition. Prentice-Hall: Englewood Cliffs, NJ.

McMurrich, J.P. 1930. Leonardo da Vinci: The Anatomist. Williams and Wilkins, Publ.: Baltimore, MD.

Rowe, Edward. 1992. "Bone Names". The Kansas School Naturalist, Vol. 38, No. 1. Emporia State University, Emporia, KS.

Shier D., J. Butler, and R. Lewis. 1996. Hole's Human Anatomy and Physiology. 7th Edition. Wm. C. Brown, Publ.: Dubuque, IA.

Singer, C. 1926. The Evolution of Anatomy, Alfred A. Knopf, Publ.: New York, NY.

Stedman, T.L. 1990. Stedman's Medical Dicitionary. 25th Edition. Williams and Wilkins: Baltimore, MD.

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