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
LOUSE Defined for Kids


noun \ˈlas\
plural lice \ˈlīs\

Definition of LOUSE for Kids

:  a small, wingless, and usually flat insect that lives on the bodies of warm-blooded animals
:  an insect or related arthropod that resembles a body louse and feeds on plant juices or decaying matter
Medical Dictionary


noun \ˈlas\
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
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