I have this from an American dictionary:-)
See 2.
It must be old (?).
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cou·ri·er
Function:
noun
1 : one that carries messages, news, or information either with urgent haste or in accordance with a regular schedule
: MESSENGER <a
courier who will carry the tidings of distress -- B.N.Cardozo> <
courier communication nearly equivalent to postal service -- F.B.Warren>: as
a : a member of a diplomatic service entrusted with bearing messages <
couriers who carry official despatches possess the right of inviolability -- G.H.Stuart>
b : an espionage agent transferring secret information;
sometimes : a runner of contraband or illicit materials
: an underworld liaison man
c : a member of the armed services whose duties include carrying mail, information, or supplies
2 : a traveler's paid attendant : a servant who facilitates travel arrangements; often : a tourists' guide employed by a travel agency
3 Canada : MAIL CARRIER
4 : a plane or other conveyance used in courier duties
http://unabridged.merriam-webster.com
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