Answer: fattest

AnswerCrossword Clue
FATTESTObesity superlative
fattestprofitable
fattestFAT, having an abundance of flesh
fattestcontaining fat
fattestoily substance found in animal tissue and many plant seeds
fattestplump
fattestthick
FATTESTBest-fed
FATTESTMost plentiful
FATTESTAdjusted "Survival of the ..."
FATTESTMost corpulent
FATTESTLike the best wallets?
FATTESTMost chubby
FATTESTWord for a sideshow member
FATTESTMost well-fed
FATTESTMost lucrative.
FATTESTMost profitable.
FATTESTMost profitable, as a business contract
FATTESTMost plump