If someone says “No Diddy” (usually used after a statement that could be seen as gay, fruity, or homo by the other person(s) in the
conversation), they are indirectly stating that the
previously stated sentence, text, etc. was not intended to be said in a
homosexual tone.
Basically, the new ‘No Homo’.
Person 1: Hey, whatcha up to today man?
Person 2: Nothing much really, about to
get in the shower then sit there naked for a while, no diddy.
Person 1: Glad you said no diddy, because for a second there, I thought you were inviting me to
have sex dude.