actually there is some subcategories(if I can call it like that) Vegeterians.
Lacto-vegetarians: who consuming milk and milk products, but not meat, eggs, fish etc.
Ovo-vegetarians: who consuming eggs, but not milk and milk products, meat, fish etc.
Marine-vegetarians: who consuming fish, but not milk and milk products, meat, eggs etc.
and Vegans who are consuming anything from animals (and their subproducts).
So a "Vegetarian" is a very general concept.