louse

/laʊs/

/laʊs/

Other forms: lice; louses

A louse is a tiny insect that lives on the skin of animals and people. If you find a louse in your hair, you'll have to treat your scalp to get rid of any of its friends that might still be lurking there.

Since they tend to travel in groups, the plural form of louse, lice, is much more common than the singular. Lice are small parasites that live on skin cells, blood, or other tiny bits of some host animal. If you're the host animal, you'll probably have an itchy head, and anyone who borrows your pillow or wears your hat will likely get lice too. A louse, informally, is also "an obnoxious person."

Definitions of louse

1. noun

   wingless usually flattened bloodsucking insect parasitic on warm-blooded animals
   synonyms: sucking louse

   types:

   Pediculus humanus, common louse

   head or body louse

   Pediculus capitis, head louse

   infests the head and body of humans

   Pediculus corporis, body louse, cootie

   a parasitic louse that infests the body of human beings

   Phthirius pubis, crab, crab louse, pubic louse

   a louse that infests the pubic region of the human body

   type of:

   insect

   a small creature with six legs, three body fragments, two antennae, and usually wings belonging in the Arthropoda phylum
2. noun

   wingless insect with mouth parts adapted for biting; mostly parasitic on birds
   synonyms: bird louse, biting louse

   types:

   Menopon gallinae, Menopon palladum, chicken louse, shaft louse

   a louse parasitic on poultry

   type of:

   insect

   a small creature with six legs, three body fragments, two antennae, and usually wings belonging in the Arthropoda phylum
3. noun

   any of several small insects especially aphids that feed by sucking the juices from plants
   synonyms: plant louse

   types:

   aphid

   any of various small plant-sucking insects

   adelgid

   any of various insects that feed and form galls on conifers

   Phylloxera vitifoleae, grape louse, grape phylloxera

   destructive to various grape plants

   jumping plant louse, psylla, psyllid

   small active cicada-like insect with hind legs adapted for leaping; feeds on plant juices

   oak blight

   a black plant louse that lives on oaks and dogwoods

   Aphis pomi, apple aphid, green apple aphid

   bright green aphid; feeds on and causes curling of apple leaves

   Aphis fabae, bean aphid, blackfly

   blackish aphid that infests e.g. beans and sugar beets

   greenfly

   greenish aphid; pest on garden and crop plants

   ant cow

   excretes a honeylike substance eaten by ants

   woolly aphid, woolly plant louse

   secretes a waxy substance like a mass of fine curly white cotton or woolly threads

   Adelges piceae, balsam woolly aphid

   a variety of adelgid

   Adelges abietis, spruce gall aphid

   a variety of adelgid

   Pineus pinifoliae, pine leaf aphid

   a variety of adelgid

   woolly adelgid

   an insect that feeds on hemlocks; its egg sacs are small fuzzy white balls like artificial snow on a Christmas tree

   type of:

   homopteran, homopterous insect

   insects having membranous forewings and hind wings
4. noun

   a person who has a nasty or unethical character undeserving of respect
   synonyms: dirt ball, insect, worm

   type of:

   disagreeable person, unpleasant person

   a person who is not pleasant or agreeable