pillar box
noun
,
British
1.
a pillarlike box in which letters are deposited for collection by mail carriers; mailbox.
Also called
pillar post
.
Origin
1855-60
British Dictionary definitions for
pillar box
pillar box
noun
1.
(in Britain) a red pillar-shaped public letter box situated on a pavement
adjective
2.
characteristic of a pillar box (in the phrase
pillar-box red
)