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indubitably

American  
[in-doo-bi-tuh-blee, in-dyoo‐] / ɪnˈdu bɪ tə bli, ɪnˈdyu‐ /

adverb

  1. in a way that is patently evident or certain; unquestionably; without doubt.

    A week at the spa has indubitably improved his health.
indubitably British  
/ ɪnˈdjuːbɪtəblɪ /

adverb

  1. without doubt; certainly

"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 indubitably

First recorded in 1620–30; indubitable ( def. ) + -ly ( def. )

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.