look up any word, like the eiffel tower:
 
1.
The act of taking a shit while facing the cistern. Causes large a mount of residual crap to be left on the bowl.
We got got kicked out of our holiday house so we busted a reversal in the tiolet then got the fuck out.
by kiwicito September 28, 2004
 
2.
to vomit or barf, particularly related to over-eating or drinking alcohol
I drank so much beer, a reversal was inevitable
by Reimer Cunningham July 07, 2005