What English uses the name for
In modern English, Ecclesiastes is almost always a book title. It names a short work of wisdom literature in the Hebrew Bible and the Christian Old Testament, the text that turns over work, pleasure, futility, and the claim that every purpose has its season. Readers sometimes stretch the name to the book's unnamed teacher, the voice that speaks those lines, but they do not use it as an ordinary common noun. A pastor is not an ecclesiastes.
The origin of the word Ecclesiastes is a chain of translations, not a native English coinage.
A Latin title in Middle English
English borrowed the name ready-made. The earliest English uses fall in the fourteenth century, some of them around 1300, and they already label that biblical book. The immediate source was church Latin: Late Latin Ecclesiastes, a transcription of Greek Ekklēsiastēs, the title chosen by the translators of the Septuagint. Middle English kept the Latin shape with little trimming. The word did not grow out of Old English; it arrived with Scripture and with the learned Latin of the Western church.
French and Anglo-Norman had related forms a little earlier. Twelfth- and thirteenth-century texts already write ecclesiaste for the book and for its speaker. English, living next to that clerical vocabulary, took the same learned form instead of inventing a Germanic title of its own.
An assembly, then a person in it
The Greek noun is built from ordinary parts. Ekklēsiastēs named someone who belonged to an ekklēsía, the civic assembly of a Greek city, above all Athens. That assembly word comes from the verb ekkalein, to call out: ek, out, plus kalein, to call, a verb that goes back to a Proto-Indo-European root for shouting. An ekklēsía was, at root, a gathering of people who had been summoned. The ending -tēs is an agent suffix, so ekklēsiastēs is a person defined by that gathering: a member of it, and in later use someone who speaks there.
The Greek title is not a sound-copy of the Hebrew name. It is a translation of an idea. The Hebrew book opens as the words of Qoheleth, also spelled Kohelet or Koheleth, a rare form from qāhāl, assembly. Qoheleth appears only in this book, about seven times, and nowhere else in the canonical Hebrew writings. Its shape looks like a feminine participle of the verb meaning to assemble, a pattern that in Hebrew can mark an office rather than a woman's identity; the verbs around it are masculine. What the office actually was is not settled. Some readings make Qoheleth the one who convenes the gathering, an officer of the qahal. Others, including the Greek translators, treat the figure as a participant in an assembly. A widespread later view takes the sense as someone who speaks before a congregation, which is how English Bibles arrived at Teacher or Preacher.
Jerome, putting the same book into Latin, used concionator, a speaker addressing a crowd. That Latin choice, more than the older Greek civic noun, helped push later European languages toward preacher.
A meaning that never quite sat still
Classical Greek did not use ekklēsiastēs for a Christian minister. The civic assembly came first. Only in late Greek did ekklēsía shift toward the Christian congregation, and only then did related words pick up a church sense. English ecclesiastic and ecclesiastical still carry that later layer: they mean of the church, not of the Athenian assembly. The book name, frozen earlier, sits a little to the side of those adjectives. It looks ecclesiastical because it shares a root, but it names a Hebrew speaker whose job was never identical with a pulpit.
That is why calling the voice the Preacher has always been a rough fit. The modern English preacher is a Christian office. The Greek word was a civic role stretched to cover a Hebrew title whose own sense remains argued over. The mismatch is the visible seam between three languages trying to name the same figure.
English also has ecclesiast, a late-medieval noun for a churchman, and a second biblical title that trips readers: Ecclesiasticus, the Latin name of Sirach, a different book. The two words share a Greek family and a similar silhouette, not an identity.
The final -es on Ecclesiastes is the Greek nominative ending, not an English plural. The book is one book. The spelling simply never got trimmed.
What other languages kept
Several European languages did not keep the Greek name. Dutch Prediker, German Prediger, and similar titles translate the preacher reading instead of transliterating Ekklēsiastēs. Hebrew still calls the book Kohelet. French Ecclésiaste, Spanish Eclesiastés, and Portuguese Eclesiastes stay closer to the Latin-Greek line that English followed.
A last distinction is easy to miss. English church does not come from ekklēsía. It comes from another Greek word, kyriakon, something belonging to the Lord. Romance languages took the assembly word into the building and the institution: French église, Spanish iglesia, Italian chiesa. English kept ekklēsía for learned church words and for this one book title, while everyday speech went another way. The name Ecclesiastes still points at a gathering that was called out, civic before it was clerical, Hebrew before it was Greek, and only then English.