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louse

[ noun lous; verb lous, louz ]
/ noun laʊs; verb laʊs, laʊz /
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See synonyms for: louse / lice / loused / lousing on Thesaurus.com

noun, plural lice [lahys] /laɪs/ for 1-3, lous·es for 4.
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 ).
any insect of the order Mallophaga (bird louse, biting louse, or chewing louse ), parasitic on birds and mammals, having mouthparts adapted for biting.
Slang. a contemptible person, especially an unethical one.
verb (used with object), loused, lous·ing.
to delouse.
Verb Phrases
louse up, Slang. to spoil; botch: Miscasting loused up the movie.
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Origin of louse

First recorded before 900; 1910–15 for def. 4; Middle English lous(e), luse, plural lise, lice; Old English lūs, plural lȳs; cognate with Dutch luis, German Laus, Old Norse lūs
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

How to use louse in a sentence

British Dictionary definitions for louse

louse
/ (laʊs) /

noun plural lice (laɪs)
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 manRelated adjective: pedicular
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
any of various similar but unrelated insects, such as the plant louse and book louse
plural louses slang an unpleasant or mean person
verb (tr)
to remove lice from
(foll by up) slang to ruin or spoil

Word Origin for louse

Old English lūs; related to Old High German, Old Norse lūs
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for louse

louse
[ lous ]

n. pl. lice (līs)
Any of numerous small, flat-bodied, wingless biting or sucking insects of the orders Mallophaga or Anoplura, many of which are external parasites on humans.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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