A person following a vegetarian diet is called a Shakahari:
Shakahara - Of a diet which excludes meat, fish, fowl and, for but a small percentage, eggs. Vegetarianism is a principle of health and environmental ethics that has been a keystone of certain religious groups in Indian life for thousands of years. The practice is widespread for the purposes of good health, as religious practice, and as a manner of fasting, as well.