Green’s Dictionary of Slang

half-tiz n.

[SE half + tizzy n.1 ]

(N.Z.) threepence.

[Aus]Bulletin (Sydney) 14 Jan. [letter from Loafer, Tauranga] Red Page n.p.: Following are other local money-names [...] 3d. – thrum, half-tiz, tray or tray-piece.