Definition of diddling:
(v) :
(transitive, slang) To cheat; to swindle.
(v) :
(transitive) To waste time.
(v) :
(transitive, slang) To masturbate.
(v) :
(transitive, slang) To molest.
(n) :
(slang, childish, countable) The penis.
(n) :
(slang, uncountable) Gin (the drink).