Alcoholism (also called alcohol dependence, ethylism, dipsomania, polydipsia, drunkenness, alcohol addiction or alcoholism) is the dependence on the psychotropic substance of potable alcohol. The procurement and consumption of alcohol increasingly define the addict's life. Continuing loss of control of drinking behaviour is typical, up to compulsive consumption, neglect of earlier interests in favour of drinking, denying addictive behaviour, withdrawal symptoms in the case of reduced consumption, tolerance to alcohol ("ability to hold your drink")  and changes in personality. 
The diagnosis systems ICD-10 and DSM-IV differentiate between alcohol dependence syndrome (F10.2 and/or 303.90) and harmful use of alcohol / alcohol abuse (F10.1 and/or 305.00). The latter – as a weaker variant of abuse behaviour – describes alcohol consumption with a demonstrably harmful effect (physical or mental), without dependence being present.
The number of people who suffer from alcoholism, and the social and economic damages caused as a result of this, are higher many times over in absolute numbers in Europe and the USA -–alongside the damage to health caused by tobacco consumption – than with other, illegal drugs. 7.4% of health problems and premature cases of death in Europe are traced back to alcohol. Therefore, the illness is in third place as the cause of premature death after tobacco consumption and high blood pressure It is also the most frequent cause of death in young men in the EU.
» continued on Wikipedia (alcoholism)