unmentionable

[ uhn-men-shuh-nuh-buh l ]
/ ʌnˈmɛn ʃə nə bəl /

adjective

not mentionable; inappropriate, unfit, or improper for mention, as in polite conversation; unspeakable.

noun

something that is not to be mentioned: That subject was classed among the unmentionables.
unmentionables,
  1. undergarments.
  2. (formerly) trousers or breeches.

Origin of unmentionable

First recorded in 1820–30; un-1 + mentionable

OTHER WORDS FROM unmentionable

un·men·tion·a·ble·ness, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for unmentionable

British Dictionary definitions for unmentionable

unmentionable
/ (ʌnˈmɛnʃənəbəl) /

adjective

  1. unsuitable or forbidden as a topic of conversation
  2. (as noun)the unmentionable

Derived forms of unmentionable

unmentionableness, noununmentionably, adverb
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