sief 

Denial that one, has any knowledge of what they are doing. (Similar to Sif but with more emphasise on the newb factor)

Sief ud miss that rail newb sk!

sief by sok August 26, 2003

Siefer Math 

The math used to determine whether or not Outbound is up or down on cases.

Utilizing Siefer Math, Outbound cases are up 1,738 even though carton length was 25-inches with Scotts on three lines and big Sterilite on the other with tile and four-foot Philips coming through CCS.

Siefer Math by LLD-NLD-4419 June 22, 2018

Siefkes 

A gentle kiss to the tip of the penis

A great way to end the night is with a siefkes.

Siefkes by bloodlake August 20, 2014

Siefly 

Tribes 1 playing legend. Who thinks that by bossing people around he is somehow on a higher plane of integence.

22:35 <SieFly> G - LD, Aliz - HO, Leo - Cap, Stone - HO, me LD, xer - lo, tb - LD, empz - ld

Siefly by Guigsy September 30, 2003

siefen 

a very good friend and a cool person to have around. gives immaculate dark academia vibes. have u seen him if without that stupid hat on? he’s weird he’s a weirdo.

hey siefen thanks for giving me ur left kidney and 1 million dollars after my house burnt down and my wife left me and i got fired

siefen by amirmendozaaaa November 22, 2021

siefert 

sensitive, compassionate, understanding, reasonable

after saving the kitten from the tree the people commented that it was a real siefert kind of thing.

siefert by smij.com October 4, 2010

siefer 

"Siefer" is a type of malware, usually found on MacBook Pro.
It slows down internet connections and writes its own name on websites.

Creepy weirdo.

Shit, I just got a Siefer on my Mac.

siefer by WebmasterProfessional3000 November 13, 2014