In Harry Potter and the Half-Blood Prince, by J.K. Rowling, a witch or wizard may use Dark Magic to divide their soul and hide it in other objects. The object then becomes a horcrux (plural: horcruxes). This must be done after an act of supreme evil e.g. murder. This grants them a form of immortality.
Voldemort can stay alive because he has seven horcruxes, including his body. He is the first person to have more than two.
by Pejhman July 17, 2005
A bit of rare dark magic, in which one takes a bit of their soul and hides it in an object. The soul is split by committing the greatest evil there is- murder. Very dangerous, very tricky, best not to try it unless you're willing to end up looking like Voldemort.
Tom Riddle: "I still don't quite understand how that works, though, sir."

Slughorn: "Well, you split your soul, you see, and hide part of it in an object outside the body. Then, even if one's body is attacked or destroyed, one cannot die, for part of the soul remains earthbound and undamaged. But of course, existence in such a form... few would want it, Tom, very few. Death would be preferable."
-Harry Potter and the Half-Blood Prince by J.K. Rowling

Bellatrix: "No, there are pieces of you missing!"

Voldemort: "Are you talking about my horcruxes?! Because if it wasn't for them I wouldn't even BE here right now!"
-A Very Potter Musical
by thehpexpert June 7, 2010
The word Horcrux orginates in Harry Potter and the Half-Blood Prince written by J.K Rowling. It means to rip the soul apart and place it in other objects for safe keeping.For this to happen the supreme act of evel must occur, murder. when he (Lord Voldemort) comitted his most import murders he performed the incatation which is unknown and split his soul with the power of each murder and placed those pieces of his soul in the six objects. he then hid the fragments of his soul around the world to make himself immortal, or as close as possible.
Lord Voldemort split his soul into seven horcruxes(Salazar Slytherins locket, Salazar Slytherins ring, Lord Voldemort's pet snake Nagini, Helga Hufflepuffs goblet, Lord Voldemort's diary from school *when he was known as Tom Marvolo Riddle*, something of Godric Gryffrindor's or Rowena Ravenclaw's, and then of course the piece left in his body!)
by eatsnow January 26, 2006
The offspring of a ginger(no soul) and a normal human being(full soul), resulting in only having only a partial soul, a horcrux.
Q: Did you know Tyrone and that ginger got married?

A: Yeah, they even have their own little horcrux now, he's so cute.
by N-arch April 7, 2011
When you traumatize a girl so bad that part of your soul is still fragmented on to her one; she’s still obsessed with you months or years later
Blake: “Dude Bob Horcruxed this Natalie bitch so hard”
Jett: “I don’t think he can die without her dying as well”
by Blakester04 April 13, 2021
A hooker that is on cruches.
Tito: Damn, that crazy ho is one of them horcrux's! I GOTTA GET ME SOME OF THAT!
by Master Clean January 26, 2006
The act of spreading your soul too thin by sleeping with any number of sub-standard babes.
She was a proper scum-bucket, he can't go on horcruxing like that.
by GRAFTERS4LYF July 17, 2011