Means to look at something intently. This is a hunting reference when you're staring at things with binoculars. Originally went viral when hunter Fred Eichler shot a moose with an arrow and it dropped in under 20 seconds.

Youtube- "just glassin"

And then popularized by Tom Segura and Christina P in their "Your Mom's House Podcast" where they got listeners to use "glassin" in common language, particularly when looking at drivethru menus. Tom Segura explains it on the Joe Rogan Experience which can be found on YouTube by searching, "just glassin"

when you're hungover as shit after a spending a night drunk as a skunk

verb: rapid yet heavy movement towards a specific place. Generally, towards 50 Cent, a bashment or a bedrin's yard.