Any time you smoke weed after 4:20pm. The history as to why it is PM and not AM as well is unknown, but likely arbitrary.

Alt: Slang for when a dealer takes a longer than usual amount of time to deliver your pot.
"Man, it's five o'clock and you're just now smoking up..? You're chronically late!"

or

"Usually on time, Timmy wondered why PK was chronically late with the kind he had ordered."
by Sleightflow October 22, 2012
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A medical condition where a man constantly arrives late because he has to find and purchase marijuana. Often witnessed by fully clothed, make-upped, perfumed
women who expected their date to arrive at 8, but don't see the sufferer until 11.
Woman 1: Dang, Ricky isn't here yet and it's already 11:30.

Woman 2: I told you girl, that boy suffers from Chronic Lateness.

Woman 1: Well at least he rolls up with weed.
by Dj Really Real January 30, 2010
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