also  ap*tha  n, pl  aph*thae  also  ap*thae   1  :  a speck, flake, or blister on the mucous membranes (as in the mouth or gastrointestinal tract or on the lips) characteristic of some diseases (as thrush)  2  :  one of the vesicles filled with clear serous fluid that occur in the mouth, on the udder, and in the spaces between the digits of cloven-footed animals in some diseases - usu. used in pl.  3  :  a disease (as foot-and-mouth disease) characterized by aphthae aph*thic adj 
 
   
 
Published under license with Merriam-Webster, Incorporated.  © 1997-2024.