n :  a crystalline acid C₆H₅NO₂ that is a member of the vitamin B complex occurring usu. in the form of a complex of niacinamide in various animal and plant parts (as blood, liver, yeast, bran, and legumes) and is effective in preventing and treating human pellagra and blacktongue of dogs - called also nicotinic acid  .
 
 
 
Similar sounding terms:  ni·sin 
 
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