the act of one woman engaging in sexual intercourse with two males at the same time, the two guys start out facing each other with the girl in between them and facing one leans forward as one man enters from behind while she gives the other a blowjob. a fist bump between the men must occur while in this position in order to create the arch.
1st gentleman; Hey man she's down for the threesome, let's Eiffel Tower.

2nd gentleman; Dude, show some class.... let's gateway arch!
by sternoinferno February 12, 2013
Your gateway band is the band you first listened to which completely opened up your world of music.

The band which was the beginning of you developing a decent taste in music.

Indie kids often use it to describe the first indie band they got into. But this term can apply to particular genre of music.
Guy-who-only-listens-to-commercial-rock: *listening to Nickelback*
Me: *hands him a bright eyes cd* Put down that rubbish, listen to this, and enjoy.
Guy-who-only-listens-to-commercial-rock: *listens to Bright Eyes* OMG, this is amazing! *stomps on Nickelback*

He then turns into either a pretentious indie kid, or just develops a decent taste in music. Yay

Bright Eyes was his gateway band.
by Jessica Lest July 19, 2008
Title given to a girl one dates solely to meet her more desirable friend.
Melissa was my gateway girlfriend for her hotter, smarter friend Rachel.
by traphikk October 4, 2009
A guy you hang out with for the purposes of meeting new people. There is usually little romantic interest, though you may lead him on.
"Who him? No I don't like him. He's just the gateway guy.
by I.LP.I August 11, 2012
A gateway cat is a cat that leads its owner to get multiple cats. It starts when someone adopts or buys a single cat. Eventually this person will get another cat to keep the original cat (the gateway cat) company or some other lame excuse. Before you know it, the individual has 40 something cats, is single, and appears on the show "Animal Hoarders".
Pam "I'd like to get a pet. Should I get a cat?"
Amy "NO! It isn't just a cat, it's a gateway cat. You can't have just one. Why don't you get a rabbit instead?"
by notacrazycatlady2 October 12, 2011
Gateway Douchebag
-noun phrase

1. a vaguely distasteful man who pursues young women, and persuades the women that this behavior is not only acceptable, but desirable in choice of mates.

2. a man whose behavior with woman colors their early perception about dating, usually in the negative.

3. a "Jason Levy"
Jeff: She Annie is 18. Her taste in men hasn’t been established. Creepier and creepier dudes will start thinking of her as an option, and it all starts with Vaughn. He’s a gateway douchebag.

-from (NBC Comedy Show) "Community"
by greggieG February 7, 2010
when a girl wears a buttoned shirt and doesnt button it which describes it as a gate. boobies=heaven. that makes it gate way to heaven
Alondra! Roxy! Yasidi! Claudia! Vanessa! close your gateway to heaven!
by Realmask La Joya July 20, 2010