addictive

adj. causing addiction, habit-forming

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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adj. addictive, causing addiction, habit-forming

adjective
(drug) which is habit-forming or which people can become addicted to; certain narcotic drugs are addictive
QUOTE:three quarters of patients aged 35-64 on GPs' lists have at least one major risk factor: high cholesterol, high blood pressure or addiction to tobacco Health Services Journal

1. Causing, tending to cause, able to cause, characterized by, or relating to addiction.
2. Prone to addiction.