I. ˈpōst ə l adjective
Etymology: French, from poste post, mail + -al — more at post (mail)
1. : of or relating to the posts or mails or to the post office
postal service
postal career
postal inspector
a postal agreement between governments
2. : of or relating to a system of carrying goods or passengers on a railroad for a uniform rate irrespective of distance
the postal principle
the postal tariff
3. : conducted by mail
postal chess
postal tuition
II. noun
( -s )
: postal card
drop a postal to the editor — Congressional Record
III. adjective
Etymology: from a series of incidents during the late 1980s and early 1990s in which disgruntled United States postal workers murdered co-workers or supervisors
: insanely or murderously violent — usually used in the phrase go postal