Definition of AB

: an abdominal muscle —usually used in plural

: the one of the four ABO blood groups characterized by the presence of antigens designated by the letters A and B and by the absence of antibodies against these antigens

able seaman; able-bodied seaman

[New Latin artium baccalaureus] bachelor of arts

Examples of ab in a Sentence

Recent Examples on the Web

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

The Spider-Man actor was seen on set just one day after his costar Matt Damon was photographed sporting an impressive beard and toned abs while filming scenes for the movie in Favignana, Italy. —Tommy McArdle, People.com, 27 Mar. 2025 The aches in your back, hips, and knees could be signs to work on your abs Published: Mar 21, 2025 Amber Sayer from Yoga Journal (Photo: Calin Van Paris/Canva) Amber Sayer is a fitness, nutrition, and wellness writer and editor. —Amber Sayer, Outside Online, 21 Mar. 2025 Paired with other forms of exercise, ab rollers workout your arms, abs and shoulders. —Christopher Murray, Fox News, 19 Mar. 2025 Another image captures him in white underwear against a three-way mirror, showcasing his toned physique and rock-hard abs from multiple angles. —Isabela Raygoza, Billboard, 17 Mar. 2025 See All Example Sentences for ab

Word History

Etymology

Noun (2)

Hebrew Ābh

Prefix

Middle English, from Anglo-French & Latin; Anglo-French, from Latin ab-, abs-, a-, from ab, a — more at of

First Known Use

Noun (1)

1956, in the meaning defined above

Noun (2)

circa 1771, in the meaning defined above

Noun (3)

1927, in the meaning defined above

Time Traveler

The first known use of ab was circa 1771

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Cite this Entry

“Ab.” Merriam-Webster.com Dictionary, Merriam-Webster, https:///dictionary/ab. Accessed 3 Apr. 2025.

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Last Updated: 3 Apr 2025 - Updated example sentences