year vs assemblage

year and assemblage both are nouns.

Word	Noun	Adjective	Verb	Adverb
year	Yes	No	No	No
assemblage	Yes	No	No	No

As nouns, assemblage is a hypernym of year; that is, assemblage is a word with a broader meaning than year:

Other hypernyms of year include gathering.

year (noun)	assemblage (noun)
a body of students who graduate together	the social act of assembling
the period of time that it takes for a planet (as, e.g., Earth or Mars) to make a complete revolution around the sun	a system of components assembled together for a particular purpose
a period of time containing 365 (or 366) days	a group of persons together in one place
a period of time occupying a regular part of a calendar year that is used for some particular activity	several things grouped together or considered as a whole