also  fag*o*py*ris*mus  n, pl  -risms  also  -ris*mus*es  :  a photosensitization esp. of swine and sheep that is due to eating large quantities of buckwheat (esp. Fagopyrum esculentum of the family Polygonaceae) and that appears principally on the nonpigmented parts of the skin as an intense redness and swelling with severe itching and the formation of vesicles and later sores and scabs - compare BIGHEADb HYPERICISM  .
 
 
 
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