WATS vs WATS line

WATS and WATS line both are nouns.

Word	Noun	Adjective	Verb	Adverb
WATS	Yes	No	No	No
WATS line	Yes	No	No	No

As nouns, WATS and WATS line are synonyms defined as:

WATS and WATS line: a telephone line; long distance service at fixed rates for fixed zones; an acronym for wide area telephone service

WATS (noun)	WATS line (noun)
a telephone line; long distance service at fixed rates for fixed zones; an acronym for wide area telephone service	a telephone line; long distance service at fixed rates for fixed zones; an acronym for wide area telephone service