fitness

noun

fit·​ness ˈfit-nəs How to pronounce fitness (audio)
Synonyms of fitnessnext
1
: the quality or state of being fit
2
: the capacity of an organism to survive and transmit its genotype to reproductive offspring as compared to competing organisms
also : the contribution of an allele or genotype to the gene pool of subsequent generations as compared to that of other alleles or genotypes

Synonyms of fitness

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Examples of fitness in a Sentence

a gymnastics program promoting fitness and agility in school-aged children I have to question the fitness of wearing a bright red dress to a funeral.
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 Agatha Christie penthouse, for example, comes with a fitness room, a marble bath, and a spacious terrace with a jacuzzi. — Rachel Cormack, Robb Report, 2 July 2026 The property also houses its own private theater, wine cellar, tasting room, game room, poker room and fitness center. — Colson Thayer, PEOPLE, 2 July 2026 The rucking vest has moved from military training grounds into mainstream fitness gear, and 2026 has delivered a wave of new options built for people who want to add strength and stamina to a simple walk. — Samantha Agate, Sacbee.com, 2 July 2026 On the other were work uniforms engineered for humanoids on industrial sites, spanning hazardous operations, smart farming, fitness coaching and auto maintenance. — Sj Studio, Footwear News, 2 July 2026 See All Example Sentences for fitness

Word History

First Known Use

1574, in the meaning defined at sense 1

Time Traveler
The first known use of fitness was in 1574

Phrases Containing fitness

Rhymes for fitness

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Browse Nearby Words

fitment
fitness
fit of laughter
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Cite this Entry

“Fitness.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fitness. Accessed 7 Jul. 2026.

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Medical Definition

fitness

noun
fit·​ness ˈfit-nəs How to pronounce fitness (audio)
: the capacity of an organism to survive and transmit its genotype to reproductively fertile offspring as compared to competing organisms
also : the contribution of an allele or genotype to the gene pool of subsequent generations as compared to that of other alleles or genotypes

More from Merriam-Webster on fitness

Nglish: Translation of fitness for Spanish Speakers

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