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plus-one

American  
[pluhs-wuhn] / ˈplʌsˈwʌn /
Or plus one

noun

  1. a person who accompanies someone to a party or other event when the invitation allows the invited guest to bring another person.

    I phoned Tom to ask if he would be my plus-one at the gala.


plus-one British  

noun

  1. informal a person who accompanies an invited person to a social function

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of plus-one

First recorded in 1970–75

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Plus, one journalist is going all in on AI and crypto-backed mortgages are entering the mainstream.

From The Wall Street Journal • Mar. 27, 2026

Plus, one, in their haste, nearly ran me down.

From Seattle Times • Jan. 20, 2024

Plus, one of pop’s reigning superstars, who released a particularly imperial seventh album in 2022 — everybody’s on mute until you guess who.

From New York Times • Jan. 12, 2024

Plus, one would imagine a player who has regularly thrived when he feels he has a point to prove will have extra fire in his belly after last year's chaos.

From BBC • Jan. 12, 2023

Plus, one of my clients said I have incredible vitality and exuberance.

From "The Joy Luck Club" by Amy Tan