• (a.) Having the dorsal fin spines symmetrical, and in the same line; -- said of certain fishes.
Hom'a·canth adjective [ Homo + Gr . ... a spine.] (Zoology) Having the dorsal fin spines symmetrical, and in the same line; -- said of certain fishes. 
homacanth Having the spines of the dorsal and anal fins situated symmetrically.