1. Vitally important; essential.

2. Misused to express awe, difficulty, or pain, probably arising from some moron that meant "excruciating", but was too much of a semiliterate fucktard to understand the difference. Countless other mentally vacant punks have adopted this misuse of the word, thus advertising their essential stupidity.
It is crucial to understand that copying the mistakes of others only makes you unoriginal as well as idiotic.
by Thanatos  February 28, 2010
of extreme importance or significance; essential
Sorry dude, that dunk was in no way crucial to anything, as good or as hard as it may have been.

That test was crucial to me passing the grade, but it was hard, so I think I failed.
by W¡ll¡ªM May 28, 2003
Ambiguous term; (adj) used to describe "serious" situations or reactions, usually following "that's" when describing a situation
If you fell down a flight of stairs, that would be crucial.
You hungry but you're broke, that's crucial!
Bruh she likes you!!! That's CRUCIAL!!!
by CrucialDuck850 November 26, 2014
1. Necessary, vital.

2. An obnoxious slang word that surfaced roughly 2 years ago and will not fucking die, along with "phat," "crunk," and Snoop Dogg-esque "izzle" talk. Even more annoying in its condensed form, pronounced "croosh." Usually applied to describe situations or objects in stupid and totally illogical ways.
I really wish dumbasses hadn't bastardized the definition of the word "crucial" and used it purely to describe something that is actually necessary to the given situation.

"YO MAN, I was fucking this phat ass bitch, it was so crucial."

"That's my boy Joe, he's crucial."

"This apple juice is crucial."

"I'm a fucking idiot who uses the word crucial."
by baybid April 18, 2005
Also used as a noun to describe how important and nesessary something is.
by sammyp November 30, 2005
Refers to an action, event, or object that is far beyond amazing. This word is spreading like wild-fire.
Ah shit bro....that dunk was crucial!
by Mack D & Dor January 25, 2003
1. An adjective used to describe something really cool
2. Can also be used to describe a difficult situation
1. That burnout was crucial! You left serious marks on the street.
2. Man, that test was way too crucial. I think I failed it.
by jbark January 30, 2003