- first-class mail as a noun:
- 1
first-class mail
noun
1 first-class mail
Mail that includes letters and postcards and packages sealed against inspection.
synonyms: 1st-class mail, 1st class, first class.
debug info: 0.0281
noun
Mail that includes letters and postcards and packages sealed against inspection.
synonyms: 1st-class mail, 1st class, first class.
debug info: 0.0281