monday fever 

when everything is extra difficult because it's monday.

dude1: "hey, whats 2+3?"

dude2: "eh.....4?"

dude1:"jesus, you got a case of monday fever!"

monday fever by godloveseveyone January 24, 2011

Monday fever 

An illness that affects metal workers and welders. Named because you build a tolerance but the weekend break allows you to be susceptible to the metal fumes again. So it is most commonly felt on monday. Also known as metal fume fever

I got Monday fever from welding earlier and now I got the shakes.

Monday fever by NowWithEctasy May 11, 2019