anorexia (n.)

1590s, "morbid want of appetite," Modern Latin, from Greek anorexia, from an- "without" (see an- (1)) + orexis "appetite, desire," from oregein "to desire, long for," literally "reach out (one's hand), stretch oneself, stretch out for" (from PIE root *reg- "move in a straight line") + abstract noun ending -ia. In current use, often short for anorexia nervosa.