Origins
The word 'preface' entered English in the late fourteenth century from Old French 'preface,' which derived from Medieval Latin 'praefatia,' an alteration of the classical Latin noun 'praefātiō.' This Latin word meant 'a saying beforehand' or 'a preliminary formula,' and it was formed from the verb 'praefārī,' composed of 'prae-' (before) and 'fārī' (to speak, to say).
The Latin verb 'fārī' is a deponent verb — passive in form but active in meaning — that belonged to everyday Latin speech. It comes from the Proto-Indo-European root *bʰeh₂-, meaning 'to speak' or 'to say,' a root that generated an extraordinary number of English words through both Latin and Greek channels. From the Latin side: 'fable' (a thing spoken, a story), 'fame' (what is spoken about someone), 'fate' (what has been spoken by the gods, a divine decree), 'affable' (easy to speak to), 'infant' (one unable to speak), 'profess' (to declare publicly), and 'confess' (to acknowledge). From the Greek cognate 'phēmí' (I say) and 'phēmē' (speech, rumor): 'euphemism' (a good saying), 'blasphemy' (harmful speech), 'prophet' (one who speaks forth), and 'phoneme' (a unit of speech sound, though this last word involves a different but related Greek root).
In classical Latin, 'praefātiō' had a specific liturgical meaning. Roman priests would utter a 'praefātiō' — a ritual formula spoken before a sacrifice or ceremony. This sacred usage carried into Christian Latin, where the 'Praefatio' became a fixed part of the Mass: the prayer spoken before the central Eucharistic prayer, introducing the most sacred portion of the liturgy. The Catholic Mass still includes a 'Preface' before the Sanctus, preserving the word's oldest ritual function.
French Influence
The secular sense — an introduction to a book — developed in parallel. Roman writers occasionally used 'praefātiō' for the introductory remarks of a literary work, though 'prooemium' (from Greek) was more common in classical usage. By the medieval period, 'praefatia' had become the standard Latin term for a book's introduction, and Old French borrowed it accordingly.
In English literary tradition, the preface became a distinctive genre in itself. Samuel Johnson's 'Preface to Shakespeare' (1765) is a masterpiece of literary criticism. William Wordsworth's 'Preface to Lyrical Ballads' (1800) effectively launched the Romantic movement. George Bernard Shaw's prefaces, often longer than the plays they introduced, became famous for their wit and argumentative force. The preface offered a space where an author could step outside the work and address the reader directly — an act of speaking before the main performance.
The distinction between 'preface' and related terms like 'introduction,' 'foreword,' and 'prologue' is often blurred in practice, but publishing convention distinguishes them. A 'preface' is typically written by the author and explains the book's purpose or genesis. A 'foreword' is written by someone other than the author. An 'introduction' deals with the book's subject matter. A 'prologue' belongs to the narrative itself. All four words encode the idea of coming before — Latin 'prae-,' Anglo-Saxon 'fore-,' Latin 'intro-,' and Greek 'pro-' — but the specific conventions differ.
Later History
The verb 'to preface' (to introduce or begin with a preliminary remark) appeared in the seventeenth century, extending the word's reach. One can preface a speech with an anecdote, preface criticism with praise, or preface bad news with reassurance. In each case, the etymological image holds: one speaks before the main event.
The word thus preserves a chain of meaning stretching from Proto-Indo-European *bʰeh₂- (to speak) through Latin ritual formulae through medieval book culture to the modern publishing convention — a quiet word that has been introducing larger works for over two thousand years.