Green’s Dictionary of Slang

filthy n.1

[SE filthy lucre]

(US) money.

[US]Eve. World (NY) 15 Dec. 4/2: The Kibosh and the Skewgee. This thing of skewgeeing cheques is getting to be too miscellaneous. Alderman Parks put the skewgee on a check for $4000 [...] and, owing to the skewgee, the drawee could not get the filthee.