louse

[ noun lous; verb lous, louz ]

noun

, plural lice [lahys] lous·es

1. any small, wingless insect of the order Anoplura sucking louse, parasitic on humans and other mammals and having mouthparts adapted for sucking, as Pediculus humanus humanus body louse or Pediculus humanus capitis head louse and Phthirius pubis crab louse, or pubic louse.
2. any insect of the order Mallophaga bird louse, biting louse, or chewing louse, parasitic on birds and mammals, having mouthparts adapted for biting.
3. plant louse.
4. Slang. a contemptible person, especially an unethical one.

verb (used with object)

, loused, lous·ing.

1. to delouse.

verb phrase

1. Slang. to spoil; botch:

   Miscasting loused up the movie.

louse

/ laʊs /

noun

1. any wingless bloodsucking insect of the order Anoplura: includes Pediculus capitis ( head louse ), Pediculus corporis ( body louse ), and the crab louse, all of which infest man pedicular
2. biting louse or bird louse
   any wingless insect of the order Mallophaga, such as the chicken louse: external parasites of birds and mammals with biting mouthparts
3. any of various similar but unrelated insects, such as the plant louse and book louse
4. slang.
   louses an unpleasant or mean person

verb

1. to remove lice from
2. slang.
   foll by up to ruin or spoil

Word History and Origins

Origin of louse¹

First recorded before 900; 1910–15 louse fordef 4; Middle English lous(e), luse, plural lise, lice; Old English lūs, plural lȳs; cognate with Dutch luis, German Laus, Old Norse lūs

Word History and Origins

Origin of louse¹

Old English lūs; related to Old High German, Old Norse lūs

Example Sentences

The human louse is a wingless, blood-sucking parasite that lives its entire life on its host.

From Science Daily

A genetic analysis based on louse DNA revealed the existence of two distinct clusters of lice that rarely interbred.

From Science Daily

These people then spread south into Central America, where modern louse populations today still retain a genetic signature from their distant Asian ancestors.

From Science Daily

“We can see the louse DNA reflected in our own history.”

From Science Magazine

For instance, only a single louse in the study came from Africa and relatively few came from South America, she notes, limiting the authors’ ability to infer how lice from around world relate to one another.

From Science Magazine