Green’s Dictionary of Slang

labonza n.

also labonz
[? Ital. la pancia, the paunch]

1. the pit of the stomach.

in Jevne & Purcell Joe Palooka [film script] I hit him right in the labonza! [HDAS].
[US]I. Wolfert Tucker’s People (1944) 97: ‘Quite a kick in the labonza,’ said Murray.
[US]Mad mag. Mar. 9: You’re going to get it in the labonza.
[US]P. Roth Human Stain 101: Coleman caught him in what Doc Chizner called ‘the labonz’.

2. the buttocks.

[US]cited in Wentworth & Flexner DAS (1975) 311/1: The day’s losses – $39,374! Quite a kick in the labonza.
[US]Mad mag. Feb. 7: Hoboy ist das kapitan gegungen zu getten it! ... Ja boy ... Right im der labonza!
[US]Trimble 5000 Adult Sex Words and Phrases.
[US]B. Rodgers Queens’ Vernacular.
[US]R.O. Scott Gay Sl. Dict. 🌐.