main file vs master file

main file and master file both are nouns.

Word	Noun	Adjective	Verb	Adverb
main file	Yes	No	No	No
master file	Yes	No	No	No

As nouns, main file and master file are synonyms defined as:

main file and master file: (computer science) a computer file that is used as the authority in a given job and that is relatively permanent

main file (noun)	master file (noun)
(computer science) a computer file that is used as the authority in a given job and that is relatively permanent	(computer science) a computer file that is used as the authority in a given job and that is relatively permanent