a messenger, usually traveling in haste, bearing urgent news, important reports or packages, diplomatic messages, etc.
2.
any means of carrying news, messages, etc., regularly.
3.
the conveyance used by a courier, as an airplane or ship.
4.
Chiefly British. a tour guide for a travel agency.
Origin: 1350–1400; < MF cour(r)ier < It corriere, equiv. to corr(ere) to run (< L currere) + -iere < L -ārius-ary; r. ME corour < AF cor(i)our, OF coreor < LL curritor runner; see current, -tor