bend vs change shape

bend is a noun but change shape is not a noun.

Word	Noun	Adjective	Verb	Adverb
bend	Yes	No	Yes	No
change shape	No	No	Yes	No

As verbs, change shape is a hypernym of bend; that is, change shape is a word with a broader meaning than bend:

Other hypernyms of bend include change form, deform.

As verbs, change shape is a hypernym of bend; that is, change shape is a word with a broader meaning than bend:

Other hypernyms of bend include change form, deform.

bend (noun)	change shape (noun)
curved segment (of a road or river or railroad track etc.)
diagonal line traversing a shield from the upper right corner to the lower left
movement that causes the formation of a curve
an angular or rounded shape made by folding
a circular segment of a curve

bend (verb)	change shape (verb)
cause (an object) to assume a crooked or angular form	assume a different shape or form
bend a joint
form a curve
change direction
turn from a straight course, fixed direction, or line of interest
bend one's back forward from the waist on down