gather vs sew together

gather is a noun but sew together is not a noun.

Word	Noun	Adjective	Verb	Adverb
gather	Yes	No	Yes	No
sew together	No	No	Yes	No

As verbs, sew together is a hypernym of gather; that is, sew together is a word with a broader meaning than gather:

Other hypernyms of gather include run up, sew, stitch.

gather (noun)	sew together (noun)
the act of gathering something
sewing consisting of small folds or puckers made by pulling tight a thread in a line of stitching

gather (verb)	sew together (verb)
increase in amount by collecting or gathering	fasten by sewing; do needlework
increase or develop
conclude from evidence
assemble or get together
draw together into folds or puckers
look for (food) in nature
draw and bring closer
collect in one place
get people together