Synonyms and Antonyms for 1st-class_mail

1. 1st-class mail (n.)

mail that includes letters and postcards and packages sealed against inspection

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2. 1st (adj.)

indicating the beginning unit in a series

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3. first-class mail (n.)

mail that includes letters and postcards and packages sealed against inspection

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4. third-class mail (n.)

mail consisting of printed matter qualifying for reduced postal rates

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