The Collaborative International Dictionary
Ichthyopterygium
Ichthyopterygium \Ich`thy*op`te*ryg"i*um\, n. [NL., fr. Gr. 'ichqy`s, -y`os, a fish + ? a fin.] (Anat.) The typical limb, or lateral fin, of fishes.
Wiktionary
ichthyopterygium
n. (context anatomy English) The typical limb, or lateral fin, of fishes.