louse
UK: laʊs | US: laʊs
n. a small, wingless, parasitic insect that infests the skin or hair of humans and animals
n. (slang) a contemptible or unpleasant person
The word "louse" traces back to Old English lūs, derived from Proto-Germanic lūs, which is also the ancestor of similar words in other Germanic languages (e.g., German Laus, Dutch luis). Its roots extend further to Proto-Indo-European lewH-, meaning "to cut, shred," likely referencing the insect's biting behavior. The word has retained its core meaning as a parasitic insect for millennia, with its slang usage ("contemptible person") emerging later as a metaphorical extension.
The child scratched his head vigorously, worried he might have a louse.
Farmers often treat livestock to prevent louse infestations.
(Slang) Don’t trust him—he’s a real louse.
Lice spread quickly in crowded living conditions.
She used a special shampoo to eliminate the louse from her hair.