noun acra·sin \ə-ˈkrā-sən\

Definition of acrasin



  1. :  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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Origin and Etymology of acrasin

New Latin Acrasiales acrasiales + 1-in

First Known Use: 1947

Seen and Heard

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to criticize severely

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