Instant Messenger-speak for a really bad joke. Comes from the Simpson's episode where Bart goes to the school for the gifted and the teacher has the class solve a math joke in which the solution is R derivative, R squared or RDRR. Example: jimmydodgeball: Well, that's what your mom said. dpstyles97: RDRR
RDRR
Meaning of RDRR in English
Slang English vocab. Английский сленговый словарь. 2012