First class and Marvelous

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

Marvelous and first class are semantically related. in good topic. In some cases you can use "Marvelous" instead an adjective phrase "First class", when it comes to topics like pleasant, fine, impressive, excellent.

Marvelous adjective - Causing wonder or astonishment.

First class and marvelous are semantically related. Sometimes you can use "First class" instead an adjective "Marvelous".