1 definition by MultiChem
In the act of Performing Oral sex on a Female, You tightly squeeze your lips together and Then Press them against the vagina Pushing air against it, making the "motorboat" effect usually used on the Breasts.
"Tania invited me over to her house last night and for dessert she totally let me Blumble her Brains out!"
by MultiChem April 13, 2010