acrasin

noun

acra·​sin ə-ˈkrā-sᵊn How to pronounce acrasin (audio)
plural acrasins
: a substance (such as cyclic AMP) that is secreted by myxamoebae of various cellular slime molds (such as those of the genus Dictyostelium or Acrasis) and that functions as a chemotactic agent attracting and causing the aggregation of similar amoeboid cells into a pseudoplasmodium
The cells are not only oriented by … acrasin, but induced to secrete it; they thus relay the orienting signals.—B. M. Shaffer, Nature, 12 June 1975

Word History

Etymology

New Latin Acrasiales acrasiales + -in entry 1

First Known Use

1947, in the meaning defined above

Time Traveler
The first known use of acrasin was in 1947

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Rhymes for acrasin

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Browse Nearby Words

Acrasieae
acrasin
Acrasis
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Cite this Entry

“Acrasin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/acrasin. Accessed 31 Oct. 2025.

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