alcoholism: habitual intoxication; prolonged and excessive intake of alcoholic drinks leading to a breakdown in health and an addiction to alcohol such that abrupt deprivation leads to severe withdrawal symptoms
drug addiction: an addiction to a drug (especially a narcotic drug)
vole: any of various small mouselike rodents of the family Cricetidae (especially of genus Microtus) having a stout short-tailed body and inconspicuous ears and inhabiting fields or meadows