gemellus

noun
ge·​mel·​lus | \ jə-ˈme-ləs How to pronounce gemellus (audio) \
plural gemelli\ -​ˌlī How to pronounce gemelli (audio) \ also gemelluses

Medical Definition of gemellus

: either of two small muscles of the hip that insert into the tendon of the obturator internus:
a : a superior one originating chiefly from the outer surface of the ischial spine

called also gemellus superior

b : an inferior one originating chiefly from the ischial tuberosity

called also gemellus inferior