Origin of prefatoryfrom Classical Latin praefatus (see preface) + -ory
Origin of prefatoryFrom Latin praefātus past participle of praefārī to say before ; see preface .
(comparative more prefatory, superlative most prefatory)
Rather formal and academic - preliminary is less formal, while introductory is less formal still. Casual alternative is to use some from of start, as in “To start..." or “Let me start by saying...", as opposed to “By way of prefatory remarks...".
1670s, from Medieval Latin *praefator +"Ž -ory (“agent"), from Medieval Latin prefatia (whence preface), for classical Latin praefatio (“a saying beforehand") - see preface for details.
Note that this is borrowed from Latin, not derived in English from preface, as in occasional misspelling *prefecatory.