noun
louse
LOUSS/laʊs/
A tiny insect that lives parasitically on another animal.
The louse lies caught on the comb with all six legs exposed.

Etymology
Old English lus already named the parasitic insect. The modern word retains that literal meaning for the pest found on human hair and skin.
In context
scratching his crotch, fishing out a louse and crushing it. It set me itching all over
More examples
- The school nurse checks the children for head lice.
- Some lice live among a bird's feathers.
- She uses a fine-toothed comb to remove lice from his hair.
Forms
louse · lice
delouse verb — To remove lice from someone or something.
Similar words
- parasite
- A broader term covering organisms that live at a host's expense.