(roh-muhn spahy-der duhmp)
1. (noun) An act of questionably sexual behavior involving a pair of male participants (one seated in traditional posture on a toilet with second said participant sitting on the lap of the other participant facing in the opposite direction) and the subsequent act of simultaneous defecation (aka "dumping"). The derivation of the term "spider" refers to the 8 arms/legs and multiple eyes of the collective parties involved. The term "Roman" means absolutely nothing.

2. (verb) The act of performing a Roman spider dump
Hey!! We both have to dump before catching that train..but there is only one toilet!! Maybe we should have a Roman spider dump to save time.
by bonedogg January 23, 2007
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