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underarm

American  
[uhn-der-ahrm] / ˈʌn dərˌɑrm /

adjective

  1. of, situated, or for use under the arm or in the armpit.

    an underarm deodorant.

  2. underhand.

    an underarm pitch in softball.


noun

  1. armpit.

adverb

  1. underhand.

underarm British  
/ ˈʌndərˌɑːm /

adjective

  1. (of a measurement) extending along the arm from wrist to armpit

  2. sport of or denoting a style of throwing, bowling, or serving in which the hand is swung below shoulder level

  3. below the arm

"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

adverb

  1. in an underarm style

"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 underarm

First recorded in 1810–20; under- + arm 1

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.

But Moutet reeled off four straight games from 0-3 down, throwing in some underarm serves, dropshots and tweeners for good measure.

From Barron's • Jan. 23, 2026

Frenchman Corentin Moutet defended his tactics Sunday after serving underarm on match-point against home hope Tristan Schoolkate at the Australian Open.

From Barron's • Jan. 18, 2026

The bowler must ask the striker if he or she is ready and then yell "play" as the jingling ball is delivered underarm with at least one bounce.

From Barron's • Nov. 22, 2025

The ball jingles and is bowled underarm along the pitch.

From BBC • Nov. 21, 2025

He raises his arm and fans his underarm odor toward me.

From "Finding Junie Kim" by Ellen Oh