internal oblique muscle

in·ter·nal ob·lique mus·cle

(in-tĕr'năl ō-blēk' mŭs'ĕl) Origin, iliac fascia deep to lateral part of inguinal ligament, anterior half of crest of ilium, and lumbar fascia; insertion, tenth to twelfth ribs and sheath of rectus; some of the fibers from inguinal ligament terminate in the conjoint tendon; action, diminishes capacity of abdomen, flexes lumbar vertebral column (bends thorax forward); nerve supply, lower thoracic.
Synonym(s): musculus obliquus internus abdominis [TA] .