Alaska crab vs Alaskan king crab

Alaska crab and Alaskan king crab both are nouns.

Word	Noun	Adjective	Verb	Adverb
Alaska crab	Yes	No	No	No
Alaskan king crab	Yes	No	No	No

As nouns, Alaska crab and Alaskan king crab are synonyms defined as:

Alaska crab and Alaskan king crab: large edible crab of northern Pacific waters especially along the coasts of Alaska and Japan

Other synonyms of Alaska crab include Alaska king crab, king crab, Paralithodes camtschatica.

As nouns, Alaska crab and Alaskan king crab are synonyms defined as:

Alaska crab and Alaskan king crab: meat of large cold-water crab; mainly leg meat

Other synonyms of Alaska crab include Alaska king crab, king crab.

Alaska crab (noun)	Alaskan king crab (noun)
large edible crab of northern Pacific waters especially along the coasts of Alaska and Japan	large edible crab of northern Pacific waters especially along the coasts of Alaska and Japan
meat of large cold-water crab; mainly leg meat	meat of large cold-water crab; mainly leg meat