addiction

n. devotion to a certain habit, dependency

An addiction is a recurring compulsion by an individual to engage in some specific activity, despite harmful consequences to the individuals health, mental state or social life. The term is often reserved for drug addictions but it is sometimes applied to other compulsions, such as problem gambling, compulsive overeating, and hyperreligiosity Factors that have been suggested as causes of addiction include genetic, biological/pharmacological and social factors.
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Addiction is a persistent, compulsive dependence on a behavior or substance. The term has been partially replaced by the word [more]Addiction - Community and Resources

Noun
1. being abnormally tolerant to and dependent on something that is psychologically or physically habit-forming (especially alcohol or narcotic drugs)
(synonym) dependence, dependency, habituation
(hypernym) physiological state, physiological condition
(hyponym) drug addiction, white plague
(derivation) addict, hook
(classification) narcotic
2. an abnormally strong craving
(hypernym) craving
3. (Roman law) a formal award by a court sentence of a thing or person to another (as of a debtor to his creditor); a surrender to a master; "under Roman law addiction was the justification for slavery"
(hypernym) award, awarding
(derivation) addict, hook
(classification) Roman law, Justinian code, civil law, jus civile

n. addiction, devotion to a certain habit, dependency