addiction in WordNet English dictionary

1. (Roman law) a formal award by a magistrate of a thing or person to another person (as the award of a debtor to his creditor); a surrender to a master
   "under Roman law addiction was the justification for slavery"
   addiction 
   
2. an abnormally strong craving
   addiction 
   
3. being abnormally tolerant to and dependent on something that is psychologically or physically habit-forming (especially alcohol or narcotic drugs)
   addiction  dependence  dependance  dependency  habituation