Nutritionist: 1) In a hospital or nursing home, a person who plans and/or formulates special meals for patients. It can also simply be a euphemism for a cook who works in a medical facility but who does not have extensive training in special nutritional needs. 2) In clinical practice, a specialist in nutrition. Nutritionists can help patients with special needs, allergies, health problems, or a desire for increased energy or weight change devise healthy diets. Some nutritionists in private practice are well- trained, hold a degree and are licensed. Depending on state law, however, a person using the title may not be trained or licensed at all.