1. to make or become fat or fatter; to increase in weight or body mass
2. to feed (livestock) to increase weight before slaughter
Usage: agriculture
3. to make richer, more profitable, or more substantial
Usage: figurative

Examples

• The rich diet will fatten the cattle quickly.
• She gained weight and fattened up during the winter months.
• The company fattened its profits by cutting costs.
• Farmers fatten their pigs before bringing them to market.
• Too much candy will fatten your waistline.
• The investment fattened his bank account considerably.