A dumbo drop is similar to a rusty trombone. It is where you are receiving a handjob while the person is licking or eating out your asshole. However, what makes it a dumbo drop is the act of defecating while they are doing this.
Man, this girl last night was nasty. While she was giving me a rusty trombone I had to shit so I decided... fuck it... I'll just dumbo drop her.
by TheRealSuperAIDS July 17, 2009
Get the Dumbo Dropmug. 
when one walks around with their pockets inside out and their primary male sexual organ hanging out of their unzipped pants whilst making elephant noises.
by Colagum November 6, 2013
Get the Dumboingmug.