- to make fat, or plump, as by feeding; specif., to make (cattle, etc.) fat for slaughter
- to make (land) fertile
- to make richer, fuller, etc.
verbfat·tened, fat·ten·ing, fat·tens
- To make plump or fat.
- To fertilize (land).
- To increase the amount or substance of: fatten one's bank account.
(third-person singular simple present fattens, present participle fattening, simple past and past participle fattened)
From fat + -en.