elan vs keenness

elan and keenness both are nouns.

Word	Noun	Adjective	Verb	Adverb
elan	Yes	No	No	No
keenness	Yes	No	No	No

As nouns, keenness is a hypernym of elan; that is, keenness is a word with a broader meaning than elan:

Other hypernyms of elan include avidity, avidness, eagerness.

elan (noun)	keenness (noun)
enthusiastic and assured vigor and liveliness	thinness of edge or fineness of point
distinctive and stylish elegance	a quick and penetrating intelligence
a feeling of strong eagerness (usually in favor of a person or cause)	a positive feeling of wanting to push ahead with something