when you convince someone that they've done something or gone somewhere (like the grand canyon) by fabricating a memory of it by telling them things you've done that you've told them about before
an example of grand canyoning:
person 1: dude do you remember when we went on a trip to florida?
person 2: no i've never been to florida
p1: remember? the lady at that gas station said they didn't know what our state was (happened to p1, but not p2)
p2: oh yeahhhhhh!! i remember that now (was told that story by p1 years ago)
p1: see, we went to florida
p2: yea i remember
person 1: dude do you remember when we went on a trip to florida?
person 2: no i've never been to florida
p1: remember? the lady at that gas station said they didn't know what our state was (happened to p1, but not p2)
p2: oh yeahhhhhh!! i remember that now (was told that story by p1 years ago)
p1: see, we went to florida
p2: yea i remember
by cheese demon June 3, 2019
Get the grand canyoningmug. 
by N0_zxne March 4, 2024
Get the Trabari Grandemug. A sex act where the male farts in the females mouth and then the female blows out the fart from her mouth into a fire that ignites the fart blown out from her mouth.
by _123345_ July 26, 2021
Get the the finnish grand dragonmug. When you piss and shit in between your partners ass cheeks then proceed give them a extra rough rim job so it looks like your eating a extra large taco
My girlfriend gave me a grand junction beef taco in my sleep last night so I made her participate in the weekly San Francisco steam train with the boys
by anonymous July 11, 2024
Get the Grand junction beef tacomug. 
Take a Dab, take a shot of liquor, take a bong rip of weed, chug a beer, and exhale. All in one breathe makes the "granny grand slam". First performed by a youtube "grandma". Taking the "strikeout" to the next level.
by Walleyewacker11 September 26, 2018
Get the Granny Grand slammug.