-ation \-a"tion\ [L. -ationem. See -tion.]

A suffix forming nouns of action, and often equivalent to the verbal substantive in -ing. It sometimes has the further meanings of state, and that which results from the action. Many of these nouns have verbs in -ate; as, alliterate -ation, narrate -ation; many are derived through the French; as, alteration, visitation; and many are formed on verbs ending in the Greek formative -ize (Fr. -ise); as, civilization, demoralization.

Source: Webster's Revised Unabridged Dictionary (1913)