• (n.) An ear tuft of feathers, as in the horned owls.
Plu'mi·corn noun [ Latin pluma feather + cornu horn.] (Zoology) An ear tuft of feathers, as in the horned owls. 
plumicorn 1. An ear tuft of feathers, as in the horned owls. 2. A horn-like tuft of feathers on a bird's head.