bird louse

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. See biting louse.

Century Dictionary and Cyclopedia

1. n. One of a kind of lice which infest the plumage of birds. The genera and species are numerous. They are mostly degraded parasitic insects of the order Mallophaga, and constitute most of that order.

GNU Webster's 1913

1. n. (Zoöl.) a wingless insect of the group Mallophaga, of which the genera and species are very numerous and mostly parasitic upon birds. -- Bird mite (Zoöl.), a small mite (genera Dermanyssus, Dermaleichus and allies) parasitic upon birds. The species are numerous.

WordNet 3.0

1. n. wingless insect with mouth parts adapted for biting; mostly parasitic on birds