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17.
A person's sister you will like to fuck
I told my friend he had a silf
by ApocalypticaX November 01, 2009
 
1.
Sandwich I'd Like To Fuck
That sub at Quizno's is a SILF.
by Freakinhuge May 08, 2006
 
2.
Sister I would like to fuck.
much like Milf, Gilf, Dilf(dad),Dilf (dog),Dilf(donkey)Cilf(child),Bilf,Cilf(cat)or any other farm animal.
Person 1:OH MY GOD, look at that chick.What a SILF.
Person 2: Dude, thats YOUR sister. That's nasty.
Person 1: It's called SILF for a reason dude. DUUU
by ill bang ur sister! December 08, 2004
 
3.
Site I'd Like to Fuck
UrbanDictionary is SILF
by An0nymous..... June 07, 2009
 
4.
Shirt I'd Like to Fuck
"BustedTees aint SILF..."
by An0nymous..... June 07, 2009
 
5.
sister i'd like to fuck

(same concept as milf)
that silf lives in your house?!?
by Spyder January 05, 2003
 
6.
Sheep I'd Like To Fuck

Commonly Used in Wales
Welsh Farmer: oh, thats a mighty fine sheep
Welsh Farmer b: yes it is a silf.
by ROBERT SAVAGE July 08, 2006
 
7.
Sandwich I'd Like To Fuck

A Sandwich made so perfectly one would be able to fornicate with previously mentioned sandwich.
"Oh man, that was such a good sandwich I'd basically call that a S.I.L.F."

Guy 1: "dude I just had the best S.I.L.F."
Guy 2: "What?"
Guy 1: "SANDWICH I'D LIKE TO FUCK!"
by JoJo Martinez September 29, 2006