: a chemical compound (such as a drug, pesticide, or carcinogen) that is foreign to a living organism
xenobiotic adjective

Word History

Etymology

xeno- + -biotic

First Known Use

1965, in the meaning defined above

Time Traveler
The first known use of xenobiotic was in 1965

Browse Nearby Words

Cite this Entry

“Xenobiotic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/xenobiotic. Accessed 8 Jul. 2026.

Medical Definition

: a chemical compound (as a drug, pesticide, or carcinogen) that is foreign to a living organism
xenobiotic adjective
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