genetics

noun

ge·​net·​ics jə-ˈne-tiks How to pronounce genetics (audio)
plural in form but singular in construction
1
: a branch of biology that deals with the heredity and variation of organisms
2
: the genetic makeup and phenomena of an organism, type, group, or condition
geneticist noun

Word History

First Known Use

1905, in the meaning defined at sense 1

Time Traveler
The first known use of genetics was in 1905

Cite this Entry

“Genetics.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/genetics. Accessed 9 Sep. 2025.

Kids Definition

genetics

noun
ge·​net·​ics jə-ˈnet-iks How to pronounce genetics (audio)
: a branch of biology that deals with the inherited traits and variation of organisms

Medical Definition

genetics

noun, plural in form but singular in construction
ge·​net·​ics jə-ˈnet-iks How to pronounce genetics (audio)
1
a
: a branch of biology that deals with the heredity and variation of organisms
b
: a treatise or textbook on genetics
2
: the genetic makeup and phenomena of an organism, type, group, or condition

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