Alternative spelling of icosahedron

(obsolete) The wane of the moon. / (obsolete) Curse. / (obsolete) Vengeance (in the phrases in a wanion, with a wanion, “with a vengeance”).

(biology) Having a similar evolutionary origin; homologous. / (mathematics) Having to do with homology. / (grammar) Of an adjective, describing itself.

plural of visual aid