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Mr. Right

noun
  1. a man who is viewed as an ideal romantic partner or potential spouse (sometimes used with Miss, Ms., or Mrs. instead of Mr. when referring to a female).

Origin of Mr. Right

First recorded in 1920–25
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for mr right

Mr Right

noun
  1. informal the man considered by a woman to be her perfect marriage partner
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