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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.

Not so at the lavish evenings hosted by law firms, where I happily tagged along as the plus-one of first- and second-year associates.

From The Wall Street Journal • Dec. 17, 2025

Unclear if a plus-one for Melania was included.

From Los Angeles Times • Jun. 23, 2025

Her daughter Emily Killian, a 43-year-old public school educator, was there as her plus-one.

From Slate • Oct. 17, 2024

A growing number of wedding guests are bringing a new kind of plus-one to the festivities: their remote jobs.

From Seattle Times • Nov. 26, 2023

According to Nan, she was a born loner but always blessed with a plus-one, first my daddy and now me.

From "Hope Springs" by Jaime Berry