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"
"I see these dudes glassin' at my whip."

Or

"I'm just glassin' at this menu for a minute. Thanks mommy."
by Justache April 30, 2018
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verb: rapid yet heavy movement towards a specific place. Generally, towards 50 Cent, a bashment or a bedrin's yard.
Ah blud, i waz glassin' down the street to Laydee Tingz yard when sum1 busted a cap in my ass!
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The preferred packaging envelope for heroin, also popular with jewelers and philatelics (stamp collectors). Glassine bags are non stick and do not promote condensation and are easilly stamped with a logo in order to promote brand recognition.
I had to stop at the head shop to pick up some more glassine bags because I used the last box to bag up a a few bricks.
by Scandall May 25, 2008
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