What is another word for fatten up?
Pronunciation: [fˈatən ˈʌp] (IPA) 
There are several synonyms for the phrase "fatten up," including plump up, beef up, bulk up, add weight, thicken up, and fill out. Each of these terms refers to the act of increasing an animal's or person's weight, usually by consuming additional food or undergoing physical activity. While some of these synonyms may be more commonly used in certain contexts, such as bodybuilding or livestock management, all convey the same basic meaning of adding weight and mass. Whether you're looking to fatten up your livestock for market or simply want to add some muscle to your frame, these synonyms provide a range of options to choose from.
