Onion Dome 

When you receive head from a guy/girl with bad breath.

She ate an onion bagel and followed it with a hot dog, now that's some onion dome.

Onion Dome by Esoquo July 20, 2007

onion cum 

When a female gives a male oral sex with french onion dip in her mouth, and the male ejaculates into her mouth.

Oh baby, I love watching you slirp up that onion cum.

onion cum by onionjoe September 11, 2016

onion cutter 

The ring around your inner asshole. Depending on how much your ass gets fucked varies in the size of the onion

Dude! Your onion cutter looks like an octopus mouth.

onion cutter by Powerfulgreen March 2, 2018

Onion Fart 

A fart that hangs around for a long period of time and has multiple layers of smell.

Sorry, I went to Oktoberfest last night, those sausages always give me onion fart the next day.

Onion Fart by Jerff March 25, 2018

Onion Baby 

Pokay

You little onion baby infant looking ass onion

Onion Baby by Moonarata July 23, 2019

Onion Sombrero 

The onion sombrero is a condom made of finely sliced onion peels.

People generally use these types of condoms to remove stank odours from different orifices or as a kinky way to do the nasty.

It is apparently very popular in Eastern European countries where normal condoms are considered too expensive.

"Either stop your wimpering or I'm going to do you with the onion sombrero!"

"Hey man, she so dirty, she like the onion sombrero"

"Hey I got Jasdouche to take the onion sombrero up his anus last night. I sure cleaned that place up!"

Onion Sombrero by JasminLikesDouches July 29, 2009

Onion Babies 

Nonsensical filler material added to a school paper to take up space, with the hopes it will go unnoticed because the paper is not actually read by the teacher for grading.

I could only write 3 pages, so i filled up the other 2 with onion babies."

Onion Babies by B. Lightningflask April 21, 2011