n 1  :  the action or process of forming pits (as in acned skin, a tooth, or a dental restoration)  2  :  the formation of a depression or indentation in living tissue that is produced by pressure with a finger or blunt instrument and disappears only slowly following release of the pressure in some forms of edema .
 
 
 
Similar sounding terms:  hy·po·ton·ic 
 
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