Green’s Dictionary of Slang

kettlebelly n.

(US) a fat person.

[US]Ariz. Sentinel (Yuma Co., AZ) 2 Dec. 1/3: When the animal turned his Gatling gun upon the crowd about two dozen men took refuge behind Kettle Belly Brown.
[US]F.H. Hart Sazerac Lying Club 87: I was [...] smokin a four-bit cigar that Kettle-belly Brown had just treated me to.
[US]M. Bodenheim Georgie May 11: Did they give you rubbish and call it sweet, these kettle-bellied, rancidly kind owners of the earth?
[US]R.F. Adams Cowboy Lingo 178: ‘Kettle-Belly’ Johnson was a noted character of Arizona who received his name from the contour of his body.