The general state of laziness experienced by seniors in high school. It often occurs near the end of the school year when their remaining time is essentially pointless, as many have already been accepted into colleges/universities. It is accompanied by a lack of studying, caring, or effort.
Junior: Aren't you going to study for your calculus test tomorrow?

Me: Nah, senior slack has hit me hard. You'll get the feeling next year...
by Bid D. Scrawl July 25, 2013
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