di·e·tet·ic \|dīə|ted.]ik, -et], ]ēk\adjective alsodi·e·tet·i·cal\]ə̇kəl, ]ēk-\ Etymology: Late Latin diaeteticus, from Greek diaitētikos, from diaita diet + -ētikos -etic, -etical — more at diet 1.: of or relating to diet or the kind and quantity of food to be eaten < dietetic rules > : belonging to dietetics < dietetic studies > 2.: adapted (as by elimination or sugar or salt) for use in special diets < dietetic sweets > < a dietetic canned tuna >