This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

adj. Having heavy or sagging jowls.

adj. Having conspicuous jowls.

adj. having sagging folds of flesh beneath the chin or lower jaw

"And for example, the dog has a "jowly" mouth on the sides where it sort of droops."

fat   

jowliness   

Cowley    Paoli   

mild-looking    oily-looking    stoop-shouldered    boy-faced    tear-wet    dapper-looking    wrynecked    liver-spotted    unshaved    kind-faced