From WordNet (r) 3.0 (2006) [wn]:
mission
n 1: an organization of missionaries in a foreign land sent to
carry on religious work [syn: mission, missionary post,
missionary station, foreign mission]
2: an operation that is assigned by a higher headquarters; "the
planes were on a bombing mission" [syn: mission, {military
mission}]
3: a special assignment that is given to a person or group; "a
confidential mission to London"; "his charge was deliver a
message" [syn: mission, charge, commission]
4: the organized work of a religious missionary [syn: mission,
missionary work]
5: a group of representatives or delegates [syn: deputation,
commission, delegation, delegacy, mission]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Mission \Mis"sion\, n. [L. missio, fr. mittere, missum, to send:
cf. F. mission. See Missile.]
1. The act of sending, or the state of being sent; a being
sent or delegated by authority, with certain powers for
transacting business; comission.
[1913 Webster]
Whose glorious deeds, but in these fields of late,
Made emulous missions 'mongst the gods themselves.
--Shak.
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2. That with which a messenger or agent is charged; an
errand; business or duty on which one is sent; a
commission.
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How to begin, how to accomplish best
His end of being on earth, and mission high.
--Milton.
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3. Persons sent; any number of persons appointed to perform
any service; a delegation; an embassy; as, the Russian
mission to the United Nations.
[1913 Webster +PJC]
In these ships there should be a mission of three of
the fellows or brethren of Solomon's house. --Bacon.
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4. An assotiation or organization of missionaries; a station
or residence of missionaries.
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5. An organization for worship and work, dependent on one or
more churches.
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6. A course of extraordinary sermons and services at a
particular place and time for the special purpose of
quickening the faith and zeal participants, and of
converting unbelievers. --Addis & Arnold.
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7. Dismission; discharge from service. [Obs.]
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Mission school.
(a) A school connected with a mission and conducted by
missionaries.
(b) A school for the religious instruction of children not
having regular church privileges.
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Syn: Message; errand; commission; deputation.
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From The Collaborative International Dictionary of English v.0.48 [gcide]:
Mission \Mis"sion\, v. t.
To send on a mission. [Mostly used in the form of the past
participle.] --Keats.
[1913 Webster]