Naming of Muscles

Learning the names of muscles can be very confusing or even overwhelming for someone learning this information for the first time. Learning the names and locations of the bones and their parts will significantly help in learning the names, locations and actions of the muscles. Prior to learning the muscles I would suggest you familiarize yourself with or study directional terms & body planes, the skeletal system as well as bone markings prior to skeletal muscles. Below is a chart of characteristics used when naming muscles.

NameDefinitionExample
 Direction of Muscle Fascicles 
RectusParallel to mid-lineRectus Abdominus
TransversePerpendicular to mid-lineTransversus Abdominus
ObliqueDiagonal to mid-lineExternal Oblique
 Size of Muscles 
MaximusLargestGluteus Maximus
MinimusSmallestGluteus Minimus
LongusLongAdductor Longus
BrevisShortAdductor Brevis
LatissimusWidestLatissimus Dorsi
LongissimusLongestLogissimus Capitis
MagnusLargeAdductor Magnus
MajorLargerPectoralis Major
MinorSmallerPectoralis Minor
VastusHugeVastus Lateralis
 Shape of Muscles 
DeltoidTriangularDeltoid
TrapeziusTrapezoidTrapezius
SerratusSerratedSerratus Anterior
RhomboidDiamond shapedRhomboid Major
OrbicularisCircularOrbicularis Occuli
PectinateComb-likePectinius
PiriformisPear shapedPiriformis
PlatysFlatPlatysma
QuadratusSquareQuadratus Femoris
GracilisSlenderGracilis
 Action of Muscles 
FlexorDecreases a joint angleFlexor Carpi Radialis
ExtensorIncreases a joint angleExtensor Carpi Radialis
AbductorMoves a bone away from the mid-lineAbductor Pollicis Longus
AdductorMoves a bone closer to the mid-lineAdductor Longus
LevatorElevates a body partLevator Scapulae
DepressorDepresses a body partDepressor Labii Inferioris
SupinatorTurns the palm anteriorlySupinator
PronatorTurns the palm posteriorlyPronator Teres
SphincterDecreases the size of an openingExternal Anal Sphincter
TensorMakes a body part rigidTensor Fasciae Latae
RotatorRotates a bone around its longitudinal axisRotatore
 Number of Origins 
BicepsTwo OriginsBiceps Brachii
TricepsThree OriginsTriceps Brachii
QuadricepsFour OriginsQuadriceps 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