Silf 

Sister I'd LOVE to fuck

Erin's sister is SUCH a silf;)

Silf by erinssisterlover101 June 9, 2009

SILF 

A person's sister you will like to fuck

I told my friend he had a silf

SILF by ApocalypticaX November 1, 2009

silf 

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.

silf by ROBERT SAVAGE July 8, 2006

silf 

Sissy I'd Like To Fuck, S.I.L.F

"Damn, that is one SILF I would like to fuck."

silf by ChriT January 12, 2017

silf 

sister i'd like to fuck

(same concept as milf)

that silf lives in your house?!?

silf by Spyder January 5, 2003

SILF 

Slug I'd Like to Fuck
Slug as in a woman's damp pussy

Look at that girl over there, what a SILF.
I want you to rub your slug all over my bald head.

SILF by seacull16 June 16, 2018

silf 

Senator I'd like to fuck.

Kristen Gillibrand is a silf.

silf by Crazyhat Williams April 20, 2009