Redonkulous can be said to be the top of the hilarity word scale as defined already by redonkulous. The word hilarious fits on this scale, however is approx. 2-3 down.
When both of these words are combined, they form one powerful super word which describes the following:
(1) An action
(2) A sound
(3) A smell
That is either
(1) Beyond normal comprehensable English language words
(2) You are laughing waay too hard to explain what your laughing at to someone
(3) Happening to someone else you don't know, and the person can visually see you and hear you laughing at them.
HAHAH, thats Redonkularious....he just saw us laughing at him !
2. Hey Simon, remember when Zimcik took a shit on those chicks lawn, and then they invited him in for drinks ! That was Redonkularious !!