louse

IPA/laʊs/
KK[lˈaʊs]IPA/laʊs/

louse — noun

  • lousesingular
  • liceplural

1. A small wingless creature that survives by feeding on the blood or skin of its h

1.nounB1
Definition

A small wingless creature that survives by feeding on the blood or skin of its host, whether human or animal, and typically causes a persistent itchy feeling.

Example

Lan found a louse in her daughter's hair after the school camping trip.

Lice spread quickly among children who share hats, combs, or pillows at school.

collocation: lice spread quickly; share hats, combs

Common collocations
  • head louse
  • body louse
  • infestation of lice
  • lice eggs
  • get rid of lice
  • check for lice
Synonyms
  • flea

    A different wingless insect that feeds on blood. Fleas jump between hosts; lice crawl and stay attached.

  • tick

    A larger parasite that buries its head in the skin to feed. Ticks are more dangerous for disease transmission.

  • mite

    A very tiny relative that is often invisible to the naked eye. Mites cause skin conditions like scabies.

Grammar Patterns

plural: lice

Usage Note

The plural form is lice (not louses). This irregular plural is essential to memorise because it is far more common in everyday use than the singular form.

Common Mistakes

There were three louses in his hair.
There were three lice in his hair.
The insect sense has an irregular plural: lice, not louses.
She found a louse egg on the brush.
She found a nit on the brush.
The eggs of lice are called nits, not louse eggs.

2. An insulting word for someone who behaves in a dishonest, selfish, or deliberate

2.nounB2
Definition

An insulting word for someone who behaves in a dishonest, selfish, or deliberately harmful way towards others.

Example

After Joaquín lied about stealing the office money, everyone called him a louse.

That louse told the boss I was late, though he himself arrived last.

pattern: That louse + verb (accusation)

Common collocations
  • you louse
  • that louse
  • such a louse
  • call someone a louse
Synonyms
  • jerk

    A more common, slightly milder insult for someone rude or unpleasant. Jerk is widely used across all registers.

  • scoundrel

    A more literary and old-fashioned term for someone morally bad. Sounds more dramatic than louse.

  • swine

    As strong as louse but less common today. Often used for greed or gluttony rather than dishonesty.

Antonyms
  • gentleman

    A man who behaves with honour and consideration — the opposite of the mean, dishonest behaviour a louse shows.

Grammar Patterns

usually singular

often preceded by 'you' or 'that'

Usage Note

In this sense the plural is louses (not lice). However, the word is almost always used in the singular, directed at one person. It is a strong insult and should be used with caution.

Common Mistakes

They are a bunch of lice.' (using insect plural for the insult sense)
They are a bunch of louses.
The insult sense takes a regular plural: louses.

louse — verb

Word family

Synonym discussion

Sense: noun/1

Louse, flea, tick, and mite are all small parasitic arthropods, but they differ in behaviour and the problems they cause. A louse (plural: lice) attaches its eggs (nits) to hair or fur and stays on the same host for its whole life. A flea jumps between hosts and bites quickly, causing sharp itching; fleas are common on pets like cats and dogs. A tick buries its head into the skin to feed on blood and can carry serious diseases such as Lyme disease. A mite is the smallest of the four — often invisible — and causes skin conditions like scabies when it burrows under the surface. For example, a child scratching their head after a sleepover likely has lice, whereas someone who hikes in tall grass should check for ticks on their body afterwards.

flea ↗tick ↗mite ↗

Common collocations

Nouns

Phrases

  • check for lice
  • get rid of lice
  • treat for lice
  • infestation of lice

Prepositions

  • louse on (a person/animal)

Etymology

Proto-Indo-EuropeanProto-GermanicOld EnglishEnglish

The word louse comes from Old English lūs, which has remained remarkably stable across thousands of years. It can be traced back through Proto-Germanic *lūs to the Proto-Indo-European root *luHs, meaning the same tiny insect. English kept the original form while many related words (like German Laus and Dutch luis) also showed little change — suggesting that humans have been dealing with lice and naming them with very similar sounds since prehistoric times.