merger vs amalgamation

merger and amalgamation both are nouns.

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

As nouns, merger and amalgamation are synonyms defined as:

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

Other synonyms of merger include uniting.

merger (noun)	amalgamation (noun)
the combination of two or more commercial companies	the combination of two or more commercial companies
an occurrence that involves the production of a union