-ation

-ation
  (-ˈeɪʃən)
  the particular form of the compound suffix -t-ion (-s-ion, -x-ion), which forms nouns of action from L. pples. in -āt-us of vbs. in -āre, Fr. vbs. in -er, and their English representatives. As mentioned under -tion (q.v.), the living form of L. -ātiōn-em in OF. was -aisun, -eisun, whence ME. -aisun, -eisun, -esun, mod. -eason, -ison; cf. ratiōn-em, reisun, reason; ōrātiōn-em, ureisun, orison. All F. words in -ation (OF. -aciun, ME. -aciun, -acioun, -acyon) were of later and literary introduction from Latin, though many of them already existed before the earliest introduction of F. words into English, where, in theological writings, passiun occurs c 1175, and sauvaciun c 1225. In French, vbs. in -er:—L. -āre, far outnumber all others; they also constitute the type on which all recent verbs are formed; hence, nouns in -ation exceed in number not only the early words in -sun, -{cced}un, -ssun, but all the other forms of -tion. In English, they number more than 1500 in modern use; the obsolete examples amount to several hundred more: see, within a few pages, apostrophation, apparation, appendication, apprecation, appunctuation, aquation, argutation, ariolation, artation, asperation, aspernation, assectation, assecuration, assedation, assemblation. A few have no accompanying verb in English use, e.g. constellation, duration, lunation, negation, oration, ovation; the great majority have a verb in -ate, e.g. cre-ate, -ation, moder-ate, -ation, satur-ate, -ation; some are formed on Gr. vbs. in -ize (of which the L. was, or would be, -īzāre, Fr. -iser), or their imitations, e.g. organize, -ation, civilize, -ation: the remainder have a vb. without suffix, derived through Fr., either with or without modification; e.g. modi-fy, -fication, appl-y, -ication, publ-ish, -ication, prove, probation; alter-ation, caus-ation, cit-ation, commend-ation, consult-ation, embark-ation, fix-ation, form-ation, not-ation, plant-ation, quot-ation, tax-ation, tempt-ation, vex-ation, visit-ation. To the mere English speaker the latter have the effect of being formed immediately on the Eng. verbs alter, cause, embark, fix, plant, tax, vex, visit, etc.; and -ation thus assumes the character of a living Eng. suffix. Hence, it comes to be applied to verbs not of Fr. origin, as in starv-ation, flirt-ation, bother-ation, backward-ation. For the meaning, see -tion; words in which -ation is, or seems to be, merely added to the verb, are synonymous with the verbal substantive in -ing; already in 17th c. the use of vexation, visitation, etc. instead of vexing, visiting, etc. (flirtation, starvation had not yet been heard of) was ridiculed thus:

Oxford English Dictionary