Naming of Muscles
Learning the names of muscles can be very confusing or even overwhelming for someone learning this information for the first time. I would suggest you study the skeletal system and bone surface markings on the understanding bones page prior to skeletal muscles as learning the names of the bones and their parts will significantly help in learning the names of the muscles. Below is a chart of characteristics used when naming muscles.
| Name | Definition | Example |
|---|---|---|
| Direction of Muscle Fascicles | ||
| Rectus | Parallel to mid-line | Rectus Abdominus |
| Transverse | Perpendicular to mid-line | Transversus Abdominus |
| Oblique | Diagonal to mid-line | External Oblique |
| Size of Muscles | ||
| Maximus | Largest | Gluteus Maximus |
| Minimus | Smallest | Gluteus Minimus |
| Longus | Long | Adductor Longus |
| Brevis | Short | Adductor Brevis |
| Latissimus | Widest | Latissimus Dorsi |
| Longissimus | Longest | Logissimus Capitis |
| Magnus | Large | Adductor Magnus |
| Major | Larger | Pectoralis Major |
| Minor | Smaller | Pectoralis Minor |
| Vastus | Huge | Vastus Lateralis |
| Shape of Muscles | ||
| Deltoid | Triangular | Deltoid |
| Trapezius | Trapezoid | Trapezius |
| Serratus | Serrated | Serratus Anterior |
| Rhomboid | Diamond shaped | Rhomboid Major |
| Orbicularis | Circular | Orbicularis Occuli |
| Pectinate | Comb-like | Pectinius |
| Piriformis | Pear shaped | Piriformis |
| Platys | Flat | Platysma |
| Quadratus | Square | Quadratus Femoris |
| Gracilis | Slender | Gracilis |
| Action of Muscles | ||
| Flexor | Decreases a joint angle | Flexor Carpi Radialis |
| Extensor | Increases a joint angle | Extensor Carpi Radialis |
| Abductor | Moves a bone away from the mid-line | Abductor Pollicis Longus |
| Adductor | Moves a bone closer to the mid-line | Adductor Longus |
| Levator | Elevates a body part | Levator Scapulae |
| Depressor | Depresses a body part | Depressor Labii Inferioris |
| Supinator | Turns the palm anteriorly | Supinator |
| Pronator | Turns the palm posteriorly | Pronator Teres |
| Sphincter | Decreases the size of an opening | External Anal Sphincter |
| Tensor | Makes a body part rigid | Tensor Fasciae Latae |
| Rotator | Rotates a bone around its longitudinal axis | Rotatore |
| Number of Origins | ||
| Biceps | Two Origins | Biceps Brachii |
| Triceps | Three Origins | Triceps Brachii |
| Quadriceps | Four Origins | Quadriceps Femoris |
| Location of a Muscle | ||
| Example: Temporalis is a muscle near the Temporal bone | ||
| Origin and Insertion of a Muscle | ||
| Example: Sternocleidomastoid (SCM) – originates on the sternum and clavicle and inserts in the mastoid process of the temporal bone |