When a woman's (or man's) rectum prolapses during anal sex.
Just as I was pulling out of her ass to blast it all over her back, she blew a Boston Redsock about the size of a filled water balloon back at me.
by The Gone Lunman March 25, 2009
Something you'll see happen to female porn stars often. It's when a really loose chick gets slammed from behind, and the outward thrust of the penis drags the vagina out with it. Thus the loose vagina makes a bright red skin sock around a guy's wang.
That girl has been to' up by everyone in town. When you fuck her she gets a really long Boston Red Sock.
by CLyn January 26, 2007
after engaging in safe sex with your girl while on her period, remove the bloody condom from your penis and slap her across the face with it, repeatedly, until she cries.
So my girlfriend told me that it was that time of the month but she was really horny. I told her not to worry, thats what condoms are made for. So i slapped one on my willy and started banging her. Exept this time I decided to pull out in the middle with the condom dripping menstral fluid and when my girlfriend looked up i began slappin her in the face with it. It took a couple seconds before she began to cry for me to stop. then i reminded her that she is from boston so she better support the boston red sock!
by Mike Grier March 21, 2006
when you put a sock on your dick while the girl is going through her period and they fuck
kayla was on her period, chad didn't have a condom, so he gave kayla a boston red sock
by ynneb June 10, 2008