toll line vs subscriber line

toll line and subscriber line both are nouns.

Word	Noun	Adjective	Verb	Adverb
toll line	Yes	No	No	No
subscriber line	Yes	No	No	No

As nouns, subscriber line is a hypernym of toll line; that is, subscriber line is a word with a broader meaning than toll line:

Other hypernyms of toll line include line, phone line, telephone circuit, telephone line.

toll line (noun)	subscriber line (noun)
a telephone line for long-distance calls	a telephone connection