amalgamation vs uniting

amalgamation and uniting both are nouns.

Word	Noun	Adjective	Verb	Adverb
amalgamation	Yes	No	No	No
uniting	Yes	No	No	No

As nouns, amalgamation and uniting are synonyms defined as:

amalgamation and uniting: the combination of two or more commercial companies

Other synonyms of amalgamation include merger.

amalgamation (noun)	uniting (noun)
the combination of two or more commercial companies	the act of making or becoming a single unit
	the combination of two or more commercial companies