Green’s Dictionary of Slang

zizz n.1

[abbr. pizzazz n.]

(US) gaiety, liveliness.

[US]Berrey & Van den Bark Amer. Thes. Sl.
[US]Gourmet Jan. 18/2: No party got into full swing until Tallulah arrived to put her particular type of zizz into it [OED].
[UK]Times 22 Feb. 12/6: The Queensgate centre lacks, perhaps, finesse and a touch of zizz.
[UK]Guardian 28 Mar. 22: Gilbert and Sullivan’s career is delightful. (If you have a little zizz).