louse

noun \ ˈlau̇s \

Definition of louse

1 plural lice play \ˈlīs\

a :any of various small wingless usually flattened insects (orders Anoplura and Mallophaga) parasitic (see parasite 2) on warm-blooded animals

b :a small usually sluggish arthropod (such as a biting louse) that lives on other animals or on plants and sucks their blood or juices

c :any of several small arthropods (such as a book louse) that are not parasitic

2 plural louses play \ˈlau̇-səz\ :a contemptible person :heel

what a beast, what a cad, what a louse he had been
—Walter Karig

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Examples of louse in a Sentence

a problem with head lice
Her ex-husband is a real louse.

Recent Examples of louse from the Web

Forever smoking his cigarettes, the husband and father takes his children to and from school, combs lice from their hair, fries sausages for their dinner.

— lisa schwarzbaum, Newsweek, "A Marriage In Crisis And An Alcoholic Father: Norway’s Karl Ole Knausgaard Returns with ‘Autumn’," 12 Aug. 2017
While sea lice aren't known for feasting on humans (they're mostly known for latching onto fish and causing severe damage), sea lice plagues have hit beaches around the world before, including in Australia and Florida.

— katina beniaris, Country Living, "Flesh-Eating Sea Creatures Attacked This Teen's Legs," 8 Aug. 2017
But the infestation and the lice hit Scarlet only in the past year, following her escape from fishing gear that had wrapped around her pectoral fin and stuck in her mouth.

— laylan connelly, The Mercury News, "Dead whale found in Southern California thought to be well-known humpback ‘Scarlet’," 23 Apr. 2017
But the infestation and the lice hit Scarlet only in the past year, following her escape from fishing gear that had wrapped around her pectoral fin and stuck in her mouth.

— laylan connelly, The Mercury News, "Dead whale found in Southern California thought to be well-known humpback ‘Scarlet’," 23 Apr. 2017
But the infestation and the lice hit Scarlet only in the past year, following her escape from fishing gear that had wrapped around her pectoral fin and stuck in her mouth.

— laylan connelly, Orange County Register, "Dead whale found near Newport Pier thought to be well-known humpback ‘Scarlet’," 21 Apr. 2017
Some are fairly straightforward; lice, for example, make their homes in human hair, and usually can only spread by crawling or falling into another person's hair with head-to-head contact.

— ben panko, Smithsonian, "Gut Check: Mandrills Sniff Poop to Avoid Peers With Parasites," 13 Apr. 2017
The policy was to immediately kick out anyone who had head lice — even in mid-haircut.

— bob shaw, Twin Cities, "Eeewww! Business of picking lice prospers in Woodbury," 25 Feb. 2017
Spiders, flies, beetles, ants, and book lice are among the critters detected in a new study, the first to evaluate arthropod diversity in U.S. homes.

— matt bertone, National Geographic, "500 Kinds of Bugs May be Living in Your House," 19 Jan. 2016

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'louse.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of louse

Middle English lous, from Old English lūs; akin to Old High German lūs louse, Welsh llau lice

NEW! Time Traveler

First Known Use: before 12th century

See Words from the same year

louse Synonyms

Synonyms

bastard, beast, bleeder [British], blighter [chiefly British], boor, bounder, bugger, buzzard, cad, chuff, churl, clown, creep, cretin, crud [slang], crumb [slang], cur, dirtbag [slang], dog, fink, heel, hound, joker, jerk, lout, pill, rat, rat fink, reptile, rotter, schmuck [slang], scum, scumbag [slang], scuzzball [slang], skunk, sleaze, sleazebag [slang], sleazeball [slang], slime, slimeball [slang], slob, snake, so-and-so, sod [chiefly British], stinkard, stinker, swine, toad, varmint, vermin

Related Words

barbarian, brute, caveman, Neanderthal, savage; loudmouth, vulgarian; lowlife, miscreant, rascal, rogue, roughneck, scab, scamp, scoundrel, villain, wretch; booby, doofus [slang], fool, jackass, nincompoop, ninny, nit [chiefly British], nitwit, nut, schmo (or schmoe) [slang]; airhead, birdbrain, blockhead, dink [slang], dolt, dope, dork [slang], goon, half-wit, idiot, imbecile, moron, turkey; brat, insolent, nuisance, pest, snip; snob, snoot, snot; dweeb [slang], nerd

Near Antonyms

hero, heroine, idol, role model; gentleman, lady; angel, saint

Other Invertebrates (Except Insects) Terms

anemone, cephalopod, quahog

louse

verb \ ˈlau̇s , ˈlau̇z \

Definition of louse

loused; lousing

transitive verb

:to remove lice from

See louse defined for English-language learners

Origin and Etymology of louse

see ¹louse

NEW! Time Traveler

First Known Use: 14th century

See Words from the same year

Other Insect Terms

drone, entomology, gadfly, pismire, proboscis, vespine

LOUSE Defined for English Language Learners

louse

noun

Definition of louse for English Language Learners

: a type of small insect that lives on the bodies of people or animals
: a bad or cruel person

LOUSE Defined for Kids

louse

noun \ ˈlau̇s \

Definition of louse for Students

plural lice \ˈlīs\

1 :a small, wingless, and usually flat insect that lives on the bodies of warm-blooded animals

2 :an insect or related arthropod that resembles a body louse and feeds on plant juices or decaying matter

Medical Dictionary

louse

noun \ ˈlau̇s \

medical Definition of louse

plural lice play \ˈlīs\

:any of the small wingless usually flattened insects that are parasitic on warm-blooded animals and constitute the orders Anoplura and Mallophaga

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See words that rhyme with louse Thesaurus: All synonyms and antonyms for louse Spanish Central: Translation of louse Nglish: Translation of louse for Spanish speakers Britannica English: Translation of louse for Arabic speakers Britannica.com: Encyclopedia article about louse

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Origin and Etymology of louse

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louse

Definition of louse

Origin and Etymology of louse

Other Insect Terms

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louse

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