Lardered

'Lardered'
To get told to smarten up your uniform by a male teacher. This involves tucking your shirt in and pulling your tie up.
Occasionally this will also involve removing non-school uniform and putting on your blazer.

boy1: what have we got next?

boy2: not sure

teacher: Oi! Get your shirts tucked in and smarten up!

boy1: ughhh...

(a few moments later)

teacher: right now if your teacher asks where you've been, tell them you got lardered

boy2: hahaha you got lardered

boy1: shut up