Synonyms/Hypernyms (Ordered by Estimated Frequency) of noun first-class

3 senses of first class

Sense 1
first class -- (the highest rank in a classification)
       => superiority, high quality -- (the quality of being superior)

Sense 2
first class, 1st class, first-class mail, 1st-class mail -- (mail that includes letters and postcards and packages sealed against inspection)
       => mail -- (the bags of letters and packages that are transported by the postal service)

Sense 3
first class -- (the most expensive accommodations on a ship or train or plane)
       => accommodation -- (living quarters provided for public convenience; "overnight accommodations are available")

Antonyms of adj first-class

1 sense of first-class

Sense 1
excellent, first-class, fantabulous, splendid -- (very good;of the highest quality; "made an excellent speech"; "the school has excellent teachers"; "a first-class mind")

INDIRECT (VIA superior) -> inferior -- (of low or inferior quality)

Similarity of adj first-class

1 sense of first-class

Sense 1
excellent, first-class, fantabulous, splendid -- (very good;of the highest quality; "made an excellent speech"; "the school has excellent teachers"; "a first-class mind")
       => superior (vs. inferior) -- (of high or superior quality or performance; "superior wisdom derived from experience"; "superior math students")

Synonyms of adv first-class

1 sense of first class

Sense 1
first class -- (by first class conveyance; with first class accommodations; "we always travel first class")