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unbirthday

British  
/ ˌʌnˈbɜːθdeɪ /

noun

  1. humorous

    1. any day other than one's birthday

    2. ( as modifier )

      an unbirthday present
"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 unbirthday

C19: coined by Lewis Carroll in Through the Looking-Glass

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.

To redeem herself and cheer up Rosa the next day, Alice hosts an intimate unbirthday celebration, a concept found in both the 1951 film and Lewis Carroll’s “Through the Looking Glass.”

From New York Times • Feb. 8, 2022

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.