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fitness

[ fit-nis ]
/ ˈfɪt nɪs /
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noun

capability of the body of distributing inhaled oxygen to muscle tissue during increased physical effort.
Also called Dar·win·i·an fit·ness [dahr-win-ee-uhn]. /dɑrˈwɪn i ən/. Biology.
  1. the genetic contribution of an individual to the next generation's gene pool relative to the average for the population, usually measured by the number of offspring or close kin that survive to reproductive age.
  2. the ability of a population to maintain or increase its numbers in succeeding generations.

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Origin of fitness

First recorded in 1570–80; fit1 + -ness
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

British Dictionary definitions for fitness

fitness
/ (ˈfɪtnɪs) /

noun

the state of being fit
biology
  1. the degree of adaptation of an organism to its environment, determined by its genetic constitution
  2. the ability of an organism to produce viable offspring capable of surviving to the next generation
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for fitness

fitness
[ fĭtnĭs ]

n.

The state or condition of being physically sound and healthy, especially as the result of exercise and proper nutrition.
A state of general mental and physical well-being.
The state of being suitably adapted to an environment.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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