initiator

noun
ini·​ti·​a·​tor | \ in-ˈish-ē-ˌāt-ər How to pronounce initiator (audio) \

Medical Definition of initiator

: one that initiates: as
a : a substance that initiates a chemical reaction
b : a substance that produces an irreversible change in bodily tissue causing it to respond to other substances which promote the growth of tumors

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Cite this Entry

“Initiator.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/initiator. Accessed 24 Jul. 2021.

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Thesaurus: All synonyms and antonyms for initiator

Britannica English: Translation of initiator for Arabic Speakers

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