(US) A former class of mail consisting mostly of heavier printed matter.
(US) A former class of mail consisting mostly of heavier printed matter.
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Of, or relating to a class of mail to be delivered before second class.
(UK) A class of postage with delivery times slower than first class.
(US) First class mail that provides the sender a proof of mailing and a delivery receipt.
(US, education) The period in school that comes after third grade and before fifth grade.
(US, education) A pupil who is in fourth grade.