鳃弓

鳃弓	sāi gōng	visceral arch (gill-bearing arch or its vestigial crease on sides of neck of vertebrates)
鳃	sāi	gills of fish
弓	Gōng	surname Gong
弓	gōng	a bow (weapon) / CL:张 / to bend / to arch (one's back etc)