Semaiternal 

Of seemingly never ending duration

Sarah and Alison's week has been Semaiternal, with the weekend seeming so far away

Semaiternal by lozzy123 August 25, 2008

Sempiternal 

Eternal and Everlasting; also coincidentally the name of the latest Bring Me The Horizon album. The title comes from a line in the song, "THIS IS SEMPITERNAL, WILL WE EVER SEE THE END? THIS IS SEMPITERNAL, OVER AND OVER AGAIN AND AGAIN."

Also a common joke that it is really "sandpit turtle".....it isn't

boy: "Wow, that new BMTH album is really good!"
friend: "Yeah, I love sempiternal!"

teacher: "They saw that knowledge is eternal."
other teacher: "indeed, it is sempiternal!"

Sempiternal by jessica sky June 16, 2013

Sempiternal 

Eternal, endless.

It comes from Latin semper (always) and aeternus (eternal).

Time is sempiternal.

Sempiternal by Sempiternal January 3, 2010

Sempiternal 

Never Changing and Never Ending ; Eternal

"This is sempiternal
Will we ever see the end?" - Bring me The Horizon / Shadow Moses

Sempiternal by Piercethesyko June 23, 2017

Sempiternal Fangirl 

A young (commonly 11 - 14) female who claims to be a 'fan' of Bring Me The Horizon, when in reality the only Album they know/like is the band's 2013 Album Sempiternal, only like Oli Sykes (lead singer) And ignore te existance of the rest of BMTH. They will get utterly confused if you mention past Albums (when they created Deathcore genre) - This Is What the Edge of Your Seat Was Made For (2004), Count Your Blessings (2006) and Suicide Season (2008). It is advised not to approach them.

BMTH Fan: Look, there goes another Sempiternal Fangirl

Sempiternal Fangirl: omfg Oli Sykes is so f-ing hot, wanna listen to Sempiternal?

Sempiternal Fangirl by BandsCatsUnicornsAngels October 29, 2015