Green’s Dictionary of Slang

(US) stylish, neat.

1914		H. Hershfield Abie the Agent 10 Sept. [synd. cartoon strip] Now this [hat] is what I call niftick! [...] It’s mine — I’ll buy it.
1915		H. Hershfield Abie the Agent 16 June [synd. cartoon strip] I got now a niftic suit to wear for the summer.
1919		H.B. Law Air Service n.p.: I slep on a little bunk made fer some sawedoff dutchman about five feet long and Al [sic] the wire slattin made some awful niftick designs on my back and hips [HDAS].
1930		G. Milburn ‘The Dealer Gets It All’ in Hobo’s Hornbook 152: I’ve done some niftik moochin’ with the best bums on the road.
1934		Weseen Dict. Amer. Sl. 190: [College] Niftic – Strylish; neat, attractive.