Inserting penis into mouth of an unsuspecting victim, and then tightly wrapping one's legs around their head. Bonus points for performing while victim is standing up.
I horse collared Ed while he was sleeping, he woke up to quite a shock.
A derogatory name for vagina coming from the similarity in shape.
I told you Matt wouldn't fight. He's too much of a horse collar.
A Southern slang term for vagina (due to its visual resemblance in iron form), usually used in reference to a girlfriend or a big vagina, either literally or referring to a really girly guy.
Orlando Bloom is a such a horsecollar.
when your drunk and/or stupid date/girlfriend is giving a blond job to your geear shift while driving home, you simply grab her by the back of her clothes and put her in the proper place.
Chet - When I drove home last night, Betty was so plastered, she went down on the gear shift again!
Peter - Did you horse collar her this time?
Chet - Well... I got with Debbie back at the barn, but she didn't do a very good job, so, yeh, I horse collared her and made it right!
Peter - You are the man!
a vagina (either literally or in reference to a person)
Orlando Bloom is a huge horsecollar.
After defecating in a toilet you grab your female/male companion and secure her/his head face down into the toilet and close the toilet seat while perform sexual acts in her anal cavity.
"Dude, I just horse collared my wife last night"