insanely good marijuana, no particular name, it's just always amazing
Me: Yo man can i get a 1/4 of high test?
You: Sure, i havn't smoked shit that good in weeks.
#1: Old-school term for Premium/high octane fuel.
#2: Also more modernly used as slang term to note things of high quality.
#1: Fill-er-up with high test, dude...Groovy!
#2: Man, that guitar is friggin' high test! If I only had the three grand to buy it...