autacoid

noun

au·​ta·​coid ˈȯ-tə-ˌkȯid How to pronounce autacoid (audio)
: a physiologically active substance (such as serotonin, bradykinin, or angiotensin) that is produced by the body and typically has a localized effect of brief duration

Word History

Etymology

aut- + Greek ákos "cure, remedy, relief" + -oid entry 1 — more at panacea

Note: The term was introduced by the English physiologist Edward Albert Schäfer (Sharpey-Schäfer, 1850-1935) in "A Proposed Classification of Hormones," XVIIth International Congress of Medicine, London: 1913, Section II, Physiology, Part II (London: 1914), p. 21: "It is, however, advisable to have an expression which will include both hormones and chalones—both excitory [causing excitement, stimulating] and inhibitory principles. The one quality which distinguishes these principles is their drug-like effect upon the organs and tissues …A convenient Greek derivative to denote this quality is 'acoid' (from ἄκος, a remedy, as in the word panacea), and to further denote that these principles are formed within and by the body, i.e. are natural, we may employ the prefix 'aut-' (Gr. αυτός). We thus get the complete expression autacoid substance to denote any drug-like principle which is produced in or can be extracted from the internally secreting organs … ."

First Known Use

1913, in the meaning defined above

Time Traveler
The first known use of autacoid was in 1913

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Cite this Entry

“Autacoid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/autacoid. Accessed 13 Mar. 2026.

Medical Definition

autacoid

noun
au·​ta·​coid ˈȯt-ə-ˌkȯid How to pronounce autacoid (audio)
: a physiologically active substance (as a serotonin, bradykinin, or angiotensin) that is produced by the body and typically has a localized effect of brief duration
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