n 1  :  the act of helping or treating : also  :  the help or treatment given <in need of immediate medical >   2  :  an assisting person or group <a laboratory >  - compare AIDE   3  :  something by which assistance is given  :  an assisting device <a visual >  : esp  :  HEARING AID .
abbr artificial insemination by donor .
 
 
 
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