secondary vs subaltern

secondary and subaltern both are nouns.

Word	Noun	Adjective	Verb	Adverb
secondary	Yes	Yes	No	No
subaltern	Yes	Yes	No	No

As adjectives, secondary and subaltern are synonyms defined as:

Other synonyms of secondary include junior-grade, lower-ranking, lowly, petty.

secondary (noun)	subaltern (noun)
coil such that current is induced in it by passing a current through the primary coil	a British commissioned army officer below the rank of captain
the defensive football players who line up behind the linemen

secondary (adjective)	subaltern (adjective)
being of second rank or importance or value; not direct or immediate	inferior in rank or status
depending on or incidental to what is original or primary
inferior in rank or status
not of major importance
belonging to a lower class or rank