What is Register?
1.
The plume of blood that appears in a syringe chamber when injecting, suggesting that the venepuncture has been successful (Drug user slang)
Usually I can't find a vein but yesterday I got a register first go!
See
2.
An excuse used by Counter-strike players when they shoot anyother player and completely miss.
Malix ! kA0s : WOW REGISTER I SHOT HIM IN THE FACE 30 TIMES !@$@!#*&#(%^
Malix ! Fear: Dude... you missed all thirty shots.