: any of numerous wingless insects (order Mallophaga) that are parasitic especially on birds
called alsobird louse
Word History
First Known Use
1864, in the meaning defined above
Medical Definition
biting louse
noun
: any of numerous wingless insects of the order Mallophaga that are mostly parasitic on birds but sometimes on mammals, have mouths adapted to biting instead of sucking, and feed on feathers, hair, or skin of the host often causing injury