Grandslam 

A term more commonly used in the UK, it is simultaneous defecation and vomiting, usually upon oneself. Normally occurs post heavy-drinking.

Did you see that bloke who just Grandslammed in the bathroom?

Grandslam by Chewy L. May 26, 2006

Grandslam 

A Grandslam is the upgrade of a Strikeout. Whereas a Strikeout is consumed in the order of marijuana, liquor, and beer, a Grandslam is performed by conusuming a line of Cocaine to leadoff the order. So it goes line of Cocaine, Bong Rip, Shot, Beer Chug, Release smoke. Grandslam.

Jack took a shotgun last night and was a badass until Ryan outdid him by pulling out a line and introducing us to the epic grandslam.

Grandslam by big_tymer8067 December 16, 2011

grandslam 

group sex

I hit a "GRANDSLAM" last night!!!!

grandslam by me mee November 14, 2003

lumberjack grandslam 

Receiving oral sex and having your mom walk in on you.

As read on Reddit.com

Yo, last night my girlfriend was giving me head, and when my mom walked in, it turned into a lumberjack grandslam!

lumberjack grandslam by foayo December 4, 2013

lumberjack grandslam 

The act of one's mother "walking in" while one is receiving oral sex. (Originated from reddit)

Instead of knocking on my room door like she usually did before entering she just opened the door. I don't know what a mothers reaction should be in this type of situation but she started yelling at my girlfriend. When I say yelling I mean I heard her say words that I never heard her say before. She called my girlfriend a whore and said that god would damn us both to hell for our act of sin. My girlfriend at this point is in tears and she's scrambling to get on her clothes and pretty sure she left my house without her bra because she was in such a panic. My mom didn't speak to me for a month after that. She didn't ask me how my day was at school, she didn't speak to me during dinner and she didn't even ask me to go to church on Sunday with her anymore. She used to go every Sunday but I always said no. That's the angriest I have ever seen my mom and we have never spoken about it. When she finally did talk to me she said if I wanted her to ever speak with me again that I had to go to confession and confess my sins. I told her I would go but I ended up going to a Denny's and ordering their Lumberjack grandslam instead. She thinks I went to confession though. Also every time my girlfriend came over after the incident my mom would leave the house. I don't know where she went but she couldn't be in the same vicinity as her. Worst part of it all was my girlfriend didn't attempt to give me another blowjob for a year because she was so scared of my mother walking in on us.

lumberjack grandslam by cittycatroina December 4, 2013

Bisexual Grandslam 

Having had sex with 4 different genders (doesn't have to be at the same time but if you do kudos). Named similarly of the Grand Slam in tennis. Having had sex with one woman, one man, one non-binary person and one agender person. Once you have achieved this you will have leveled up your bisexuality.

"I had sex with the hottest non-binary person last night, finally achieved the Bisexual Grandslam."

Bisexual Grandslam by Jaegrr July 14, 2023

Operation Grandslam 

A crazy operation to break into Fort Knox, but not to steal anything.Instead,an "atomic device" is used to dirty the gold for 57 years.
Could not possibly work in real life.

Operation grandslam will have my undivided attention!

Operation Grandslam by Foo December 10, 2003