gymnorhinal

from The Century Dictionary.

• In ornithology, having naked nostrils: having the nostrils un-feathered: an epithet of sundry birds, especially of certain jays and auks, which are distinguished by this circumstance in their respective families, in which the nostrils are usually feathered.

from the GNU version of the Collaborative International Dictionary of English.

• adjective (Zoöl.) Having unfeathered nostrils, as certain birds.