gathering vs assembling

gathering and assembling both are nouns.

Word	Noun	Adjective	Verb	Adverb
gathering	Yes	No	No	No
assembling	Yes	No	No	No

As nouns, assembling is a hypernym of gathering; that is, assembling is a word with a broader meaning than gathering:

Other hypernyms of gathering include aggregation, collecting, collection.

gathering (noun)	assembling (noun)
the social act of assembling	the act of gathering something together
the act of gathering something
sewing consisting of small folds or puckers made by pulling tight a thread in a line of stitching
a group of persons together in one place