noun
- Mail that includes letters and postcards and packages sealed against inspection.
- synonyms: first class, 1st class, 1st-class mail
WordNet 3.0 © 2006 by Princeton University
| APA | WordNet. (2010). first-class mail. Retrieved September 20, 2026, from http://smartdefine.org/first-class_mail/definitions/1276308 |
| Chicago | WordNet. 2010. "first-class mail" http://smartdefine.org/first-class_mail/definitions/1276308 (accessed September 20, 2026). |
| Harvard | WordNet 2010, first-class mail, Smart Define, viewed 20 September, 2026, <http://smartdefine.org/first-class_mail/definitions/1276308>. |
| MLA | WordNet. "first-class mail" 23 October 2010. Web. 20 September 2026. <http://smartdefine.org/first-class_mail/definitions/1276308> |