organisation vs mission

organisation and mission both are nouns.

Word	Noun	Adjective	Verb	Adverb
organisation	Yes	No	No	No
mission	Yes	No	No	No

As nouns, mission is a hyponym of organisation; that is, mission is a word with a more specific, narrower meaning than organisation:

organisation (noun)	mission (noun)
the act of organizing a business or an activity related to a business	a special assignment that is given to a person or group
the activity or result of distributing or disposing persons or things properly or methodically	an operation that is assigned by a higher headquarters
the act of forming or establishing something	the organized work of a religious missionary
an ordered manner; orderliness by virtue of being methodical and well organized	a group of representatives or delegates
an organized structure for arranging or classifying	an organization of missionaries in a foreign land sent to carry on religious work
a group of people who work together
the persons (or committees or departments etc.) who make up a body for the purpose of administering something