What is the definition of bulimia nervosa and anorexia nervosa?

According to the American Psychiatric Association, a person diagnosed as bulimic or anorectic must have all of that disorder's specific symptoms:

Bulimia Nervosa

• recurrent episodes of binge eating (minimum average of two binge-eating episodes a week for at least three months)
• a feeling of lack of control over eating during the binges
• regular use of one or more of the following to prevent weight gain: self-induced vomiting, use of laxatives or diuretics, strict dieting or fasting, or vigorous exercise
• persistent over-concern with body shape and weight.

• refusal to maintain weight that's over the lowest weight considered normal for age and height
• intense fear of gaining weight or becoming fat, even though underweight
• distorted body image
• in women, three consecutive missed menstrual periods without pregnancy.