On to copacetic:

"co·pa·cet·ic or co·pa·set·ic (kp-stk)

adj. Excellent; first-rate; completely satisfactory"

I really like how the word 'copacetic' looks and sounds. Its too bad that that word appears to be rarely used by African Americans nowadays. Among African Americans and other 'hip' [if not hip-hop] folks, copacetic has been replaced-many times over-with words and phrases such as
"bad", "mean", "awesome", "hot", "smokin", "burnin up", "the bomb", "blew up"; "phat", "righteous", "tight"; all that", "all that and a bag of chips", "off the chart", "off the hook", "off the chain", big" {as in "got big"} ,"large" {as in "livin large", and "the shit".

I posted that list of words in the Mudcat thread thread.cfm?threadid=100282#2008953 "RE: Definition of 'square'!"

One equivalent phrase that I forgot to include in that list is "cookin". That word is a "bona fried" :o} member of the 'hot', 'burning', 'smokin' family of positive terms that I listed in that post.

An example of 'cookin' is "That band was really "cookin"- meaning they were really "getting down"; They were really playing well.

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But back to 'copacetic'. Another word that replaced 'copacetic' is 'cool'. Of course 'cool' has a number of colloquial meanings. Nut I'm speaking here of 'cool'='hip'='with it'='hot'='dynamite'='the bomb'.

Among Black Americans that meaning for cool has largely played out-meaning it got too much play since it was picked up by 'mainstream' society. [Have you noticed that often when Black slang is picked up by White folks, Black folks retire it and move on to some other terms?]

But sometime you can still hear Black people say "That's cool" {meaning "That's alright"} and not "That's great!".

And some people may also say "That's cool and the gang" {which is a takeoff of the 1970s? R&B group, Kool & The Gang.

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Here's an interesting online essay about the theories about the origin of the word 'copacetic':

http://www.pointlessart.com/education/copacetic.html