trunk call vs long distance

trunk call and long distance both are nouns.

Word	Noun	Adjective	Verb	Adverb
trunk call	Yes	No	No	No
long distance	Yes	No	No	No

As nouns, trunk call and long distance are synonyms defined as:

trunk call and long distance: a telephone call made outside the local calling area

Other synonyms of trunk call include long-distance call.

trunk call (noun)	long distance (noun)
a telephone call made outside the local calling area	a telephone call made outside the local calling area