Is gravy vegetarian? ?

No, its not vegetarian. Anything made from dead animals, whether you eat the meat or not. The same applies to things like rennet (in cheese), gelatin (jello) meat flavorings, oyster or fish sauce, or anything else that contains a dead critter or by product of one. Vegetarian means that no animal died in the process of making the ingredients, and vegan would mean it contains no animal by products whatsoever, such as dairy or eggs.