threesome

threesome — noun

1. A set of three people who are together for a shared activity, situation, or purp

1.nounB2
Definition

A set of three people who are together for a shared activity, situation, or purpose — for example, three friends travelling together, three colleagues working on a project, or three people seated at a table.

Example

A threesome of old college friends rented a beach house for the holiday weekend.

collocation: a threesome of [people] + singular verb

The restaurant seated the threesome at a quiet table near the window.

Common collocations
  • a threesome of friends
  • a threesome of colleagues
  • form a threesome
  • complete a threesome
  • join a threesome
Synonyms
  • trio

    More neutral and can describe people or things; 'trio' is preferred for musical groups and is less casual than 'threesome'.

  • triad

    More formal or technical; often used in sociology, music theory, or chemistry rather than everyday speech.

  • triplet

    Almost exclusively used for three babies born at the same birth or three matching objects; not interchangeable for general groups.

Antonyms
  • duo

    A group of two rather than three

  • foursome

    A group of four people

Grammar Patterns

a threesome of + plural noun

threesome + singular verb

Usage Note

Frequently used with 'of' to specify who makes up the group, as in 'a threesome of friends'. The verb is usually singular (a threesome was seen), though plural gets used informally.

Common Mistakes

The threesome of students were taking a break.
The threesome of students was taking a break.
In formal English, treat 'threesome' as a singular unit, not a plural group.
I met a threesome of birds in the park.
I saw a trio of birds in the park.
'Threesome' normally refers to people, not animals or objects; use 'trio' or 'set of three' for non-human groups.

2. A sexual encounter or relationship that involves three people at the same time,

2.nounC1
Definition

A sexual encounter or relationship that involves three people at the same time, typically discussed in informal or personal contexts rather than clinical writing.

Example

The magazine article explored why some couples consider having a threesome.

collocation: have a threesome; informal register

Eight percent of survey participants said they had tried a threesome.

Common collocations
  • have a threesome
  • try a threesome
  • invite someone for a threesome
  • participate in a threesome
Synonyms
  • menage a trois

    A French loan phrase meaning a household or sexual arrangement involving three people; sounds more literary or sophisticated.

Grammar Patterns

have a threesome

participate in a threesome

threesome + singular verb

Usage Note

This sense is informal and describes sexual activity. Avoid using it in formal, academic, or professional writing about relationships or sexuality — use 'group sex involving three people' or 'three-person sexual encounter' instead. In Taiwan Mandarin, 三人行 is the common informal equivalent.

Common Mistakes

The documentary discussed threesomes from a sociological viewpoint.
The documentary discussed three-person sexual encounters from a sociological viewpoint.
The informal label 'threesome' may feel out of place in serious academic writing.

3. A type of golf match with exactly three players, where one person plays a ball o

3.nounC2
Definition

A type of golf match with exactly three players, where one person plays a ball of their own while the other two share a single ball and take turns hitting it.

Example

The club scheduled a threesome because an odd number of players had arrived.

collocation: schedule a threesome

In a threesome, Apinya played her own ball while Hugo and Felipe shared one.

in a threesome + description of rules

Common collocations
  • play a threesome
  • schedule a threesome
  • in a threesome
  • a threesome match
Synonyms
  • three-ball match

    A less common term for a three-person golf game; sometimes implies each player uses their own ball.

Antonyms
  • foursome

    A golf match between two pairs of players

Grammar Patterns

play a threesome

in a threesome

Usage Note

This is a technical golf term. In most casual golf, foursomes (two pairs) are more common, and a threesome happens when an odd number of players are left. Do not confuse with 'foursome' (four players in pairs) or 'singles match' (one-on-one).

Common Mistakes

We had a threesome at the golf course — me, my father, and my brother each had our own ball.
We had a threesome
I played against my father and brother, who shared one ball between them.' — In proper golf rules, a threesome means two players share a single ball, not three separate balls.

Word family

  • three
    numeralA1
  • threefold
    adjectiveC1
  • threefold
    adverbC1

Synonym discussion

Sense: noun/1

Threesome, trio, triad, and triplet all describe a group of three, but differ in tone and typical use. Threesome feels casual and is most natural for people doing an activity together — three friends on a trip or three colleagues on a project. Trio is the most neutral and versatile: you can use it for musicians (a jazz trio), people (a trio of hikers), or objects (a trio of lamps). Triad carries formal or technical weight — sociologists study triads in group dynamics, and the word also refers to certain chords in music or criminal organisations (the Triads of East Asia), so it can mislead in everyday contexts. Triplet is extremely narrow: it means three babies born together or three identical items. For an everyday group of people doing something together, threesome and trio both work, but choose trio in writing where a neutral tone matters, and threesome when you want a slightly friendlier, spoken feel.

trio ↗triadtriplet

Common collocations

Nouns

Phrases

  • form a threesome
  • join a threesome
  • complete a threesome

Prepositions

Etymology

Old EnglishMiddle EnglishModern English

'Threesome' was formed in English by joining the number 'three' with the suffix '-some', which creates adjectives meaning 'characterised by' (as in 'handsome' or 'gladsome'). The earliest known use, from around the year 1200, was as an adjective meaning 'consisting of three' or 'threefold'. By the 1600s, it had become a noun referring to a group of three people or things. The sexual meaning appeared in the mid-1900s. The golf meaning dates from the late 1800s, when the modern rules of the sport were being formalised.