n :  compulsive physiological need for and use of a habit-forming substance (as heroin, nicotine, or alcohol) characterized by tolerance and by well-defined physiological symptoms upon withdrawal : broadly  :  persistent compulsive use of a substance known by the user to be physically, psychologically, or socially harmful - compare HABITUATION SUBSTANCE ABUSE  .
 
 
 
Similar sounding terms:  ad·duc·tion 
 
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