1ST-CLASS MAIL

I. (noun)

Meaning:

Mail that includes letters and postcards and packages sealed against inspection

Synonyms:

1st-class mail; 1st class; first-class mail; first class

Classified under:

Nouns denoting communicative processes and contents

Hypernyms ("1st-class mail" is a kind of...):

mail (the bags of letters and packages that are transported by the postal service)

Hyponyms (each of the following is a kind of "1st-class mail"):

correspondence (communication by the exchange of letters)