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.
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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.
But, even for them, there are no guarantees their fitness will last a lifetime. — Donna Vickroy, Chicago Tribune, 18 Oct. 2026 And those striving for zest under these circumstances may benefit from assistance from a mental health professional like a psychologist, a physical health provider like a physician, or a personal trainer or fitness instructor. — Joan M. Cook, Time, 17 Oct. 2026 Arrange your pass with reception to book excellent yoga and fitness classes or access to the lap pool, thermal circuit, or gym. — Condé Nast, Condé Nast Traveler, 17 Oct. 2026 The Withings Health app now charges new users to sync their weight, health, and fitness data with third-party services such as Apple Health, Google Health Connect, MyFitnessPal, and Samsung Health. — James Peckham, PC Magazine, 16 Oct. 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 20 Oct. 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
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