ˌaktəˈnistēə noun plural
Usage: capitalized
Etymology: New Latin, from actin- + -istia (from Greek histion web, cloth, sail); akin to Greek histos mast, weaver's beam, web — more at stamen
: an order (superorder Crossopterygii) of chiefly Mesozoic fishes including the family Coelacanthidae having the interspinous bones supporting each dorsal and anal fin fused into one piece — compare latimeria