Green’s Dictionary of Slang

1. to trick, to defraud, to play a confidence trick.

1935		Thieves Slang ms list from District Police Training Centre, Ryton-on-Dunsmore, Warwicks 7: Moodying: Seeking information or acting innocent.
1962		R. Cook Crust on its Uppers 21: Trying to moody through to the royal enclosure on the knock.

2. to complain.

1962

R. Cook Crust on its Uppers 22: I could go moodying on for hours about them!

3. to lie about, to act lazily.

1962

R. Cook Crust on its Uppers 22: None of this moodying about in bed all day.

4. to pretend.

1962		F. Norman in Police and the Public in Norman’s London (1969) 129: I moodied that I was hirt more than I was.
2000		J.J. Connolly Layer Cake 294: I fancy [...] hanging hard in the South of France, moodying that I’m a film producer.
2011		J.J. Connolly Viva La Madness 41: She’s pranged, but moodyin she ain’t.