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1.
A Weekend Junky is a person who would eat healthy food for most of the week, but when the weekend comes they eat nothing but junk food.

Like for weekdays their eating habits would be like a strict diet, while on the weekends they seem to toss that diet aside for just a couple of days then when Monday comes by again they are back on their diets.
Tom: At work Veronica only eats vegetables, and cheese it is hard to believe she is a weekend junky.
by BKobayashi February 27, 2011