gather vs cluster

gather and cluster both are nouns.

Word	Noun	Adjective	Verb	Adverb
gather	Yes	No	Yes	No
cluster	Yes	No	Yes	No

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

gather (noun)	cluster (noun)
the act of gathering something	a grouping of a number of similar things
sewing consisting of small folds or puckers made by pulling tight a thread in a line of stitching

gather (verb)	cluster (verb)
increase in amount by collecting or gathering	gather or cause to gather into a cluster
increase or develop	come together as in a cluster or flock
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