diet
US /ˈdaɪ.ət/
UK /ˈdaɪ.ət/

1.
the kinds of food that a person, animal, or community habitually eats
:
•
A healthy diet includes plenty of fruits and vegetables.
•
The panda's diet consists almost entirely of bamboo.
2.
a special course of food to which one restricts oneself, either to lose weight or for medical reasons
:
•
She's on a strict diet to lose weight for the wedding.
•
My doctor recommended a low-sodium diet due to my high blood pressure.
1.
restrict oneself to small amounts or special kinds of food in order to lose weight or for medical reasons
:
•
I need to start dieting if I want to fit into that dress.
•
He has been dieting for months to improve his health.