First Class

nicest and most expensive passenger section (in a plane, train, etc.); of the best quality, highest group in a classification; superior, choice, excellent

First class generally indicates a high level of service or importance. Specific uses of the term include:First class travelFirst Class mailFirst-class cricketFirst Class rank in Boy Scouting (Boy Scouts of America)First Class Diver – the highest grade of diver in the original (and now obsolete) classification system of the  British Sub Aqua Club.First class honours degree – see  British undergraduate degree classification
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Noun
1. the highest rank in a classification
(hypernym) superiority, high quality
2. mail that includes letters and postcards and packages sealed against inspection
(synonym) 1st class, first-class mail, 1st-class mail, priority mail
(hypernym) mail
(hyponym) correspondence
3. the most expensive accommodations on a ship or train or plane
(hypernym) accommodation

Adjective
1. of the highest quality; "made an excellent speech"; "the school has excellent teachers"; "a first-class mind"
(synonym) excellent, fantabulous
(similar) superior
Adverb
1. by first-class conveyance; with first-class accommodations; "we always travel first class"

n. first class

high quality, excellent Pam's meals are first class. She's an excellent cook.