bontozzler, adj. — Green’s Dictionary of Slang

bontozzler adj.

[variant of bontodger adj. / bontosher adj.with -zzler ending taken from synonymous dazzler, bobby-dazzler, sizzler]]

excellent,, first-rate.

1916		Wagga Wagga Exp. (NSW) 13 July 4/4: Brown played a real good game, and so did his skip, who rewarded every good shot with loud words of praise, such as ‘That’s real bontozzler,’ or ‘Wow-wow,’ or ‘Gosh,’ whichever expression appeared to him most appropriate.
1918		Table Talk (Melbourne) 31 Jan. 34/1: All the talk about a big, champion, bontozzler heat-wave on Saturday was moonshine.