Other forms: gratified; gratifying; gratifies
To gratify is to satisfy. Bringing home an A in math would gratify your math tutor. Gratify can also mean to give in. You probably shouldn't gratify your urge to scream in class.
Gratify comes from the Latin gratificari, "oblige," and gratus, "pleasing." The word still carries those meanings. Gratify always takes an object, so you have to gratify something or someone. Gratifying praise will make you feel good about all the work you put in on your science project. Gratify your thirst for vocabulary by using this word correctly!