noun \ˈlas\

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

: a bad or cruel person

Full Definition of LOUSE

plural lice \ˈlīs\
a :  any of various small wingless usually flattened insects (orders Anoplura and Mallophaga) parasitic on warm-blooded animals
b :  a small usually sluggish arthropod (as a biting louse) that lives on other animals or on plants and sucks their blood or juices
c :  any of several small arthropods (as a book louse) that are not parasitic
plural lous·es \ˈla-səz\ :  a contemptible person :  heel

Examples of LOUSE

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

Origin of LOUSE

Middle English lous, from Old English lūs; akin to Old High German lūs louse, Welsh llau lice
First Known Use: before 12th century

Related to LOUSE

Other Invertebrates (Except Insects) Terms

anemone, cephalopod, quahog


verb \ˈlas, ˈlaz\

Definition of LOUSE

transitive verb
:  to remove lice from

First Known Use of LOUSE

14th century

Other Insect Terms

drone, entomology, gadfly, pismire, proboscis, vespine


noun \ˈlas\   (Medical Dictionary)
plural lice \ˈlīs\

Medical Definition of LOUSE

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


noun    (Concise Encyclopedia)

Any of some 3,300 species of small, wingless, parasitic insects of the order Phthiraptera. The order consists mainly of biting, or chewing, lice (parasites of birds and mammals) and sucking lice (see sucking louse). The louse's body is flattened. The eggs, or nits, are cemented to the hair or plumage of the host, and most species spend their entire lives on the bodies of host animals. Heavy infestations cause much irritation and may lead to secondary infections. In moving from host to host, lice may spread many diseases, including tapeworm infestation in dogs and murine typhus in rats.


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