elaboration vs improvement

elaboration and improvement both are nouns.

Word	Noun	Adjective	Verb	Adverb
elaboration	Yes	No	No	No
improvement	Yes	No	No	No

As nouns, improvement is a hypernym of elaboration; that is, improvement is a word with a broader meaning than elaboration:

Other hypernyms of elaboration include advance, betterment.

elaboration (noun)	improvement (noun)
developing in intricate and painstaking detail	the act of improving something
addition of extra material or illustration or clarifying detail	a change for the better; progress in development
marked by elaborately complex detail	a condition superior to an earlier condition
a discussion that provides additional information
the result of improving something