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.
Mythical causes of altitude sickness include alcohol consumption, dehydration, and poor fitness. — Katie Hill, Outdoor Life, 3 Sep. 2026 The value of eight hours of sound sleep has become more apparent to guests in an era of meditation apps and wearable fitness trackers that monitor sleep. — Jeanne Bonner, CNN Money, 3 Sep. 2026 Some fitness enthusiasts swear that working out on an empty stomach burns more fat, while others insist that eating beforehand is essential for maximizing energy and performance. — Daryl Austin, USA Today, 2 Sep. 2026 The workout targets fat burn, cardiovascular fitness and resting metabolism. — Samantha Agate, Kansas City Star, 2 Sep. 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 4 Sep. 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
Last Updated: - Updated example sentences
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