Quick definitions from WordNet (louse)
▸ noun: wingless usually flattened blood-sucking insect parasitic on warm-blooded animals
▸ noun: any of several small insects especially aphids that feed by sucking the juices from plants
▸ noun: a person who has a nasty or unethical character undeserving of respect
▸ noun: wingless insect with mouth parts adapted for biting; mostly parasitic on birds
▸ Also see louse
▸ noun: wingless usually flattened blood-sucking insect parasitic on warm-blooded animals
▸ noun: any of several small insects especially aphids that feed by sucking the juices from plants
▸ noun: a person who has a nasty or unethical character undeserving of respect
▸ noun: wingless insect with mouth parts adapted for biting; mostly parasitic on birds
▸ Also see louse