mission in WordNet English dictionary

1. a special assignment that is given to a person or group
   "a confidential mission to London"; "his charge was deliver a message"
   mission  charge  commission 
   
2. a group of representatives or delegates
   deputation  commission  delegation  delegacy  mission 
   
3. an organization of missionaries in a foreign land sent to carry on religious work
   mission  missionary post  missionary station  foreign mission 
   
4. an operation that is assigned by a higher headquarters
   "the planes were on a bombing mission"
   mission  military mission 
   
5. the organized work of a religious missionary
   mission  missionary work