I have been sober for 3 years and was always searching for the defination of the alcoholic. Our paterns, quanities, ages, and a million other factors are differant. I have heard a lot of definations but none of them fit everyone. I have finally found one that seems to fit everyone (at least so far)
My Defination:
Some one who continues to drink despite repeated negative consequences. Normal people stop doing things that hurt, alcoholics just keep doing them thinking it will be differant this time.
Read the big book online "The chapter to the alcoholic" and the "Doctors opinion" They are short but if you see yourself you may wish to read more.