When you and your friends are in a smoking circle with the same amount of blunts or joints(idealy with different types of weed) equal to the amount of people there. After each hit they pass to the left, hence mary (weed) goes around in a full circle and nobody gets left out.
Person 1:okay we got 5 people here, 2 blunts of orange kush, 2 blunts of white ryno and 1 joint of bobby brown. Lets ride the mary go round and dont forget its puff puff pass bitches.
by Discard August 07, 2008
(noun) A sexual act that involves at least one partner with no legs, and the legless "mary" spins herself around with her own arms, while her vaginal cavity is still engaged with the males erect penis.
by Chooke May 02, 2009