Any of a group of glycoproteins of primarily plant (usually seed) origin that binds to glycoproteins on the surface of cells causing agglutination, precipitation, or other phenomena resembling the action of specific antibody; lectins include plant agglutinins (phytoagglutinins, phytohemagglutinins), plant precipitins, and perhaps certain animal proteins; some have mitogenic properties and induce lymphocyte transformation.
[L. lego, pp. lectum, to select, + -in]
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Examples: glitazone, GI cocktail, etc.