underpants

underpants — plural noun

1. a piece of clothing that you wear next to your skin under trousers or a skirt, c

1.plural nounA2
Definition

a piece of clothing that you wear next to your skin under trousers or a skirt, covering the area from your waist down to the tops of your legs.

Example

Naoko bought three new pairs of underpants at the department store yesterday.

counted with 'a pair of' for singular items

The washing machine shrank Rodrigo's favourite underpants to half their size.

possessive determiner + underpants

Common collocations
  • a pair of underpants
  • clean underpants
  • dirty underpants
  • wear underpants
  • pack underpants
Synonyms
  • underwear

    broader term that covers all types of undergarments, not only the lower body

  • pants

    common UK term for underpants; in the US 'pants' means trousers

  • knickers

    UK informal term, usually for women's underpants

  • briefs

    a specific style of underpants with short leg sections

Grammar Patterns

a pair of underpants

underpants + plural verb

Usage Note

Always plural in form. To refer to one item, use 'a pair of underpants' followed by a singular verb (e.g. 'A pair of underpants was on the floor') or a plural verb in everyday speech.

Common Mistakes

I need a new underpants.
I need a new pair of underpants.
'underpants' is always plural, so use 'a pair of' when talking about one item.
My underpants is dirty.
My underpants are dirty.
'underpants' takes a plural verb.

Word family

Synonym discussion

Sense: plural noun/1

'Underpants' refers specifically to the lower-body undergarment worn under trousers or a skirt. 'Underwear' is the broadest term — it covers everything worn under outer clothes, including bras, vests, and underpants. In British English, 'pants' is the everyday word for underpants, but in American English 'pants' means trousers, so learners should use 'underpants' to avoid confusion. 'Knickers' is a British informal term for women's underpants and can sound old-fashioned. 'Briefs' describes a particular cut of underpants with short leg sections, not the category as a whole. For example: 'I need to buy new underpants for the gym' works in any variety of English, while 'I need to buy new pants' would send an American looking in the trouser section.

underwear ↗pants ↗knickersbriefs

Etymology

Old EnglishMiddle EnglishEnglish

Formed by combining 'under-' (meaning 'below, beneath') with 'pants' (a leg-covering outer garment). The word appeared in English in the early 1800s as a specific term for undergarments worn beneath trousers, at a time when 'pants' itself was still considered a low-status word.