acra·​sin | \ ə-ˈkrā-sᵊn How to pronounce acrasin (audio) \
plural acrasins

Definition of acrasin

: 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

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First Known Use of acrasin

1947, in the meaning defined above

History and Etymology for acrasin

New Latin Acrasiales acrasiales + -in entry 1

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The first known use of acrasin was in 1947

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Cite this Entry

“Acrasin.” Dictionary, Merriam-Webster, Accessed 3 Dec. 2021.

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