convex shape vs taper

convex shape and taper both are nouns.

Word	Noun	Adjective	Verb	Adverb
convex shape	Yes	No	No	No
taper	Yes	No	Yes	No

As nouns, taper is a hyponym of convex shape; that is, taper is a word with a more specific, narrower meaning than convex shape:

Other hyponyms of convex shape include umbo, camber, entasis, knob, node, thickening, ridge, peak, point, tip, projection.

convex shape (noun)	taper (noun)
a shape that curves or bulges outward	stick of wax with a wick in the middle
	a loosely woven cord (in a candle or oil lamp) that draws fuel by capillary action up into the flame
	the property possessed by a shape that narrows toward a point (as a wedge or cone)
	a convex shape that narrows toward a point

convex shape (verb)	taper (verb)
	give a point to
	diminish gradually