heighten vs sharpen

heighten and sharpen both are verbs.

Word	Noun	Adjective	Verb	Adverb
heighten	No	No	Yes	No
sharpen	No	No	Yes	No

As verbs, sharpen is a hyponym of heighten; that is, sharpen is a word with a more specific, narrower meaning than heighten:

Other hyponyms of heighten include heat up, hot up, screw up, fan, enhance, heighten, raise, amplify, heighten.

As verbs, heighten and sharpen are synonyms defined as:

heighten (verb)	sharpen (verb)
increase the level of	become sharp or sharper
become more extreme	make crisp or more crisp and precise
make more extreme; raise in quantity, degree, or intensity	raise the pitch of (musical notes)
make more intense, stronger, or more marked	put (an image) into focus
make (one's senses) more acute	make (one's senses) more acute
increase the height of	give a point to
	make sharp or sharper
	make (images or sounds) sharp or sharper