Characteristics used to Name Muscles

Directional terms

orientation of muscle fascicles relative to body’s midline

D: Rectus

Ex)

parallel to midline

rectus femoris, rectus abdominis

D: Transverse

Ex)

Perpendicular to the midline

transversus abdominis

D: Oblique 

Ex) 

diagonal to midline 

external oblique and internal oblique 

Size

relative size of the muscle

S: Maximus

Ex)

largest

Gluteus maximus

S: Minimus

Ex) 

smallest 

gluteus minimus 

S: Longus

Ex)

long

extensor carpi radialis longus

S: Brevis

Ex) 

short

adductor brevis 

S: Latissimus

Ex)

widest

latissimus dorsi

S: Longissimus

longest

S: Magnus

Ex) 

large 

adductor magnus

S: Major

Ex)

larger

pectoralis major

S: Minor

Ex) 

smaller 

pectoralis minor 

S: Vastus

huge

vastus lateralis, medialis, and intermedius 

Shape

relative shape of muscle

SH: Deltoid

Ex

triangular 

deltoid 

SH: Trapezius

Ex)

trapezoid

trapezius

SH: Serratus

Ex)

saw-toothed

serratus anterior

SH: Rhomboid

Ex)

diamond shaped

Rhomboid minor and major

SH: Gracilis 

Ex) 

slender

gracilis 

Action

principal action of the muscle

A: Flexor

Ex)

decreases a joint angle

flexor carpi radialis

A: Extensor

Ex)

increases a joint angle

extensor carpi radialis

A: Abductor 

Ex)

moves a bone away from the midline 

abductor pollicis longus 

A: Adductor

Ex) 

moves a bone closer to the midline 

adductor longus, magnus, and brevis

A: Levator

Ex) 

raises or elevates a body part 

levator scapulae 

A: Tensor 

Ex)

makes a body part rigid 

tensor fasciae latae 

Number of origins:

number of tendons of origin

NO: Biceps

two origins

NO: Triceps

three origins

NO: Quadriceps

four origins