mission

Concise Oxford English Dictionary © 2008 Oxford University Press:
mission/ˈmɪʃn/

▶noun

• 1 an important assignment, typically involving travel abroad.

  ■ [treated as sing. or pl.] a group of people sent on a mission.

  ■ an organization or institution involved in a long-term assignment abroad.

  ■ a military or scientific expedition.

• 2 the vocation of a religious organization to spread its faith.

  ■ a building or group of buildings used by a Christian mission.

• 3 a strongly felt aim or calling.

– origin C16 (denoting the sending of the Holy Spirit into the world): from L. missio(n-), from mittere ‘send’.