fitness

noun

fit·​ness ˈfit-nəs 

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

• health
• wellness
• strength

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

Four guest bedrooms on the main level each have an attached bathroom—two also have walk-in closets—and share a cozy living area and a spa zone with a fitness room, sauna, and garden-level calm. —Abby Montanez, Robb Report, 6 Nov. 2025

Home fitness has changed dramatically in recent years. —Jason Phillips, USA Today, 6 Nov. 2025

Her fitness DVDs remain the home workouts in history, according to Red Seat. —Todd Spangler, Variety, 6 Nov. 2025

Continuing his fitness journey, the rapper successfully launched his Wunna Run Club with a 5K race event in Brooklyn’s Prospect Park, which attracted more than 1,000 runners to join Gunna in September. —Michael Saponara, Billboard, 6 Nov. 2025

Word History

First Known Use

1574, in the meaning defined at sense 1

Phrases Containing fitness

• physical fitness

Rhymes for fitness

• witness
• eyewitness
• unfitness

Medical Definition

fitness

noun

fit·​ness ˈfit-nəs 

: 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