serratus posterior

English Thesaurus

1. skeletal muscle that draws the rib cage backward and downward (noun.body)

hypernym	:	serratus, serratus muscles,
definition	:	any of several muscles of the trunk (noun.body)

hyponym	:	serratus posterior inferior,
definition	:	a thin quadrilateral muscle at the junction of the thoracic and lumbar regions; acts to counteract the pull of the diaphragm on the ribs to which it is attached (noun.body)

hyponym	:	serratus posterior superior,
definition	:	a thin quadrilateral muscle of the upper and dorsal part of the thorax; acts to elevate the upper ribs (noun.body)