symbiont

noun

sym·​bi·​ont ˈsim-bē-ˌänt How to pronounce symbiont (audio)
: an organism living in symbiosis
especially : the smaller member of a symbiotic pair

Examples of symbiont in a Sentence

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.
She is killed by Gul Dukat at the end of season 6, and her symbiont is passed on to a new host, Ezri Dax. — Chris Snellgrove, Entertainment Weekly, 25 May 2026 Lichens are symbionts, or two organisms that are in a cooperative relationship. — Elizabeth Rayne, ArsTechnica, 19 Apr. 2025 In early life, this tissue exposes developing immune cells to intestinal microbes, helping the body learn to distinguish between harmless symbionts and harmful pathogens. — Lilia Goncharova, The Conversation, 9 Mar. 2026 Any efforts to grow plants will necessarily lead to the introduction of bacteria, fungi, and other microbes — whether intentionally as useful symbionts or as accidental stowaways. — Scott E. Solomon, STAT, 22 Apr. 2026 See All Example Sentences for symbiont

Word History

Etymology

borrowed from German Symbiont, probably altered (after Greek ont-, stem of ṓn, present participle of eînai "to be") from symbiount-, stem of symbiôn, present participle of symbioûn "to live together" — more at symbiosis

First Known Use

1887, in the meaning defined above

Time Traveler
The first known use of symbiont was in 1887

Browse Nearby Words

symbion
symbiont
symbionticism
See all Nearby Words

Cite this Entry

“Symbiont.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/symbiont. Accessed 7 Jul. 2026.

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Kids Definition

symbiont

noun
sym·​bi·​ont ˈsim-ˌbī-ˌänt How to pronounce symbiont (audio)
-bē-
: an individual living in symbiosis
especially : the smaller member of a symbiotic pair

Medical Definition

symbiont

noun
sym·​bi·​ont ˈsim-ˌbī-ˌänt How to pronounce symbiont (audio) -bē- How to pronounce symbiont (audio)
: an organism living in symbiosis
especially : the smaller member of a symbiotic pair

called also symbiote

symbiontic
ˌsim-ˌbī-ˈänt-ik, -bē- How to pronounce symbiont (audio)
adjective

More from Merriam-Webster on symbiont

Britannica.com: Encyclopedia article about symbiont

Last Updated: - Updated example sentences
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