trans-Alaska pipeline vs Alaskan pipeline

trans-Alaska pipeline and Alaskan pipeline both are nouns.

Word	Noun	Adjective	Verb	Adverb
trans-Alaska pipeline	Yes	No	No	No
Alaskan pipeline	Yes	No	No	No

As nouns, trans-Alaska pipeline and Alaskan pipeline are synonyms defined as:

trans-Alaska pipeline and Alaskan pipeline: an oil pipeline that runs 800 miles from wells at Prudhoe Bay to the port of Valdez

Other synonyms of trans-Alaska pipeline include Trans-Alaska Pipeline System.

trans-Alaska pipeline (noun)	Alaskan pipeline (noun)
an oil pipeline that runs 800 miles from wells at Prudhoe Bay to the port of Valdez	an oil pipeline that runs 800 miles from wells at Prudhoe Bay to the port of Valdez