A very severe condition of being a slacker. Commonly diagnosed by continual refusal to work, be helpful, or show energy for getting things done. Unable to complete a job from start to finish. Is highly contagious in the workplace, home, or anywhere productivity is commonplace.

Some other symptoms are: Asking other employees over to your water cooler bringing them away from doing work also.(aka - slackenitis's desk to play music, talk about bands, or any other non-work related subjects)
Slackenitis:

Joshua I can't come to work today (usually on Monday or Friday), as I have headache.

BOSS Do you have some sort of medical condition causing these headaches every Monday and Friday?

Joshua Yes, I have shaky leg syndrome, which leads to headaches on Mondays and Fridays.

BOSS Please stay home, as I think you have slackenitis, and we don't want it to spread to the other employees.

(People use lots of different excuses when they have slackenitis, including: headache, son/daughter is sick, shaky leg syndrome, traffic is bad etc.)
by Supervisor August 13, 2007
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A pint or two of beer to take the edge off
Areet mate, you fancy a slackener?”
by Northu December 25, 2022
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