First class and Finest

First class noun - Mail that includes letters and postcards and packages sealed against inspection.

Finest and first class are semantically related. in best topic. In some cases you can use "Finest" instead the phrase "First class" as an adjective or a noun, when it comes to topics like top, superior, excellent, most excellent.

Finest noun - A body of officers of the law.

First class and finest are semantically related. You can use "First class" instead the word "Finest" as a noun or an adjective.