The sound indicating the presence of a doodle-smacking monster on doodle jump, used to a) warn someone else of an approaching problem b) take the piss out of an authority.
a) Chick One: Hey Gloreen, you get my homework done?
(Teacher comes into view behind Chick One's back)
Chick Two: Diddley-rum.

b) Slacker One: Manager's coming.
Slackers Two, Three and Four: Rum-diddley-rum-diddley-rum.
by grnlk May 19, 2010
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