keen vs cracking

keen and cracking both are nouns.

Word	Noun	Adjective	Verb	Adverb
keen	Yes	Yes	Yes	No
cracking	Yes	Yes	No	No

As adjectives, keen and cracking are synonyms defined as:

Other synonyms of keen include bang-up, bully, corking, dandy, great, groovy, neat, nifty, not bad, old, peachy, slap-up, smashing, swell.

keen (noun)	cracking (noun)
a funeral lament sung with loud wailing	the act of cracking something
	a sudden sharp noise
	the process whereby heavy molecules of naphtha or petroleum are broken down into hydrocarbons of lower molecular weight (especially in the oil-refining process)

keen (adjective)	cracking (adjective)
excellent	excellent
intense or sharp
having or demonstrating ability to recognize or draw fine distinctions
having a sharp cutting edge or point
painful as if caused by a sharp instrument

keen (verb)	cracking (verb)
express grief verbally