cy·​to·​tox·​ic ˌsī-tə-ˈtäk-sik How to pronounce cytotoxic (audio)
: of or relating to a cytotoxin
: toxic to cells
cytotoxic drugs

Example Sentences

Recent Examples on the Web Interestingly, the complete soup also lacked cytotoxic activity. Ncbi Rofl, Discover Magazine, 7 Mar. 2012 Then Allison and his colleagues discovered that a molecule called cytotoxic T lymphocyte antigen-4 (CTLA-4) acts as a checkpoint, or built-in brake, on T cells. Quanta Magazine, 3 Feb. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cytotoxic.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

First Known Use

1902, in the meaning defined at sense 2

Time Traveler
The first known use of cytotoxic was in 1902

Dictionary Entries Near cytotoxic

Cite this Entry

“Cytotoxic.” Dictionary, Merriam-Webster, Accessed 5 Feb. 2023.

Medical Definition


cy·​to·​tox·​ic ˌsīt-ə-ˈtäk-sik How to pronounce cytotoxic (audio)
: toxic to cells
cytotoxic lymphocytes
cytotoxic drugs
cytotoxicity noun
plural cytotoxicities
Last Updated: - Updated example sentences
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