A day spent ingesting ecstasy tablets, presumably if someone has nothing to do for that day or the next. A good way to spend a sunny day, the most successful pill days are to be had by university students in the summer term when they have no exams, no coursework, and a sunny day in a sociable and picturesque setting at their disposal. Alternatively, a good pill day can be had at music festivals when there is little or no constraint as to what you can or can't do.

Smoking green, having a few beers or ingesting other drugs can occur, but the main impetus of the day is to be knocking the little 'uns back.
"What you got planned tomorrow mate?"
"I got fuck all to do man so if it's a nice day I'm just gonna sit on the hill and have a pill day, care to join me?"
"Shit man I would but I gotta have dinner at my parents' and I don't wanna be gurning like a cunt all evening."

"Did you see Kings of Leon on the Saturday?"
"Mate, to be fair, I might have done yeh. I was fuuuuucked, my mate got his stash nicked off him on the Friday so we just decided to do shitloads of beans and nothing else on the Saturday and have a pill day which pretty much wrote off my memory - and most of Sunday."
by Seany Blitz December 7, 2009
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