资料来源 : pyDict

一等的,第一流的

资料来源 : WordNet®

first class
     n 1: the highest rank in a classification
     2: mail that includes letters and postcards and packages sealed
        against inspection [syn: {1st class}, {first-class mail},
        {1st-class mail}, {priority mail}]
     3: the most expensive accommodations on a ship or train or
        plane