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um

American  
[uhm, uhn, uhm, uhn] / ʌm, ʌ̃, əm, ə̃ /
Or umm

interjection

  1. (used as an expression of doubt, hesitation, deliberation, interest, etc.)

um 1 British  
/ ʌm, əm /

interjection

  1. a representation of a common sound made when hesitating in speech

"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
um 2 British  

abbreviation

  1. US Minor Outlying Islands

"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

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.