Is Pacific a noun

The Word 'pacific' (lower case p) is an adjective, a Word that describes a noun as conducive to peace, not aggressive (a pacific nation, pacific people, etc.).

The Word 'Pacific' (capital P) is a proper noun , the name of a specific ocean, the "Pacific Ocean".

The Word 'Pacific' (capital P) is also a proper adjective, a Word that describes a noun as of or related to the Pacific Ocean (Pacific islands, Pacific fleet, etc.).