Etymologiae, Book I, chapters 5-7: De grammatica to De nomine
Chapter V. On grammar Grammar is the science of speaking correctly, and the origin and foundation of the liberal letters. Among the disciplines it was invented after the common letters, so that those who had already learned their letters might know by it the method of correct speech. Grammar takes its name from letters (litterae). For the Greeks call letters grammata. It is called an art because it consists of the precepts and rules of art. Others say the word is drawn from the Greek aretē, that is, from virtue, which they called knowledge. Speech (oratio) is so called as if oris ratio, the reckoning of the mouth. For orare is to speak and to say. Speech is a weaving together of words with sense. A weaving without sense is not speech, because it is not the reckoning of the mouth. Speech is full in sense, voice and letter.
Some reckon the divisions of the art of grammar as thirty, that is: the eight parts of speech, articulate voice, letter, syllable, feet, accent, punctuation marks, signs, orthography, analogy, etymology, glosses, differences, barbarisms, solecisms, faults, metaplasms, schemes, tropes, prose, metres, fables, histories.
Chapter VI. On the parts of speech Aristotle was the first to hand down two parts of speech, the noun and the verb; afterwards Donatus defined eight. But all return to those two principal ones, that is, to the noun and the verb, which signify person and action. The rest are appendages and draw their origin from these. For the pronoun is born of the noun, whose office it performs, as “that orator.” The adverb is born of the noun, as doctus, docte. The participle is born of the noun and the verb, as lego, legens. The conjunction, the preposition and the interjection fall within the compass of these. Therefore some defined only five parts, because those are superfluous.
Chapter VII. On the noun The noun (nomen) is so called as if notamen, because by its word it makes things known to us. For unless you know the name, the knowledge of things perishes. Proper names are so called because they are special. For they signify the person of one only. There are four species of proper names: praenomen, nomen, cognomen, agnomen. The praenomen is so called because it is placed before the name, as “Lucius,” “Quintus.” The nomen is so called because it marks the family, as “Cornelius”; for all the Cornelii belong to that family. The cognomen, because it is joined to the name, as “Scipio.” The agnomen is as it were an additional name, as “Metellus Creticus,” because he subdued Crete. For the agnomen comes from outside, from some reason. Cognomentum, in common speech, is so called because it is added to the name for the sake of recognition, or because it is with the name. Appellative nouns are so called because they are common and consist in the signification of many. These are divided into twenty-eight species, of which the corporeal are so called because they are either seen or touched, as heaven, earth. Incorporeal, because they lack body; hence they can neither be seen nor touched, as truth, justice. General, because they belong to many things, as “animal”; for man and horse and bird are animals. Special, because they show a part, as “man”; for man is a species of animals. Principal, because they have the first position and are not born from elsewhere, as mountain, fountain. Derivative, because they are derived from another noun, as montanus from mons. Diminutive, because they diminish the sense, as Graeculus, scholasticulus. Diminutive in sound, because they sound as diminutives do but in sense are principal, as tabula, fabula. Wholly Greek, because they are declined wholly in Greek, as Callisto; for so both the Greek and the Latin say. Wholly Latin, because they are wholly turned into Latin. The Greek says Odysseus, the Latin Ulixes. Intermediate, so called because they are partly Greek, partly Latin. The same are also called bastard, because they corrupt the last syllables while the first remain, as among the Greeks Alexandros, Menandros; among us Alexander, Menander. They are called bastard (notha) in the way that anyone born of unequal stock is called nothus. Synonyms, that is, many-named, because in several names there is one signification, as terra, humus, tellus; for all are the same. Homonyms, that is, one-named, because in one name there is a manifold signification, as tumulus, now a low mountain, now swelling ground, now a sepulchre. For in one name there is a diverse signification. Relatives are so called because they are referred to another person, as master, lord, father. Those called “things which stand in a certain relation to something” are named from the contrary signification, as “right”; for “right” cannot be said unless there is a “left.” Further, names of quality are so called because by them it is shown of what sort anyone is, as wise, handsome, rich. Of quantity, because they are drawn from measure, as long, short. Patronymics are so called because they are drawn from fathers, as Tydides, son of Tydeus, Aeneius, son of Aeneas, although they are also drawn from mothers and from ancestors. Ktetic, that is, possessive, from possession, as “Evander’s sword.” Epithets, which in Latin are called adjectives or superposed, because they are added to nouns to fill out their signification, as great, learned. You add them to persons, as “a great philosopher,” “a learned man,” and the sense is full. Names of action descend from action, as leader, king, runner, nurse, orator. Names of nation come from the nation, as Greek, Roman. Names of country descend from the country, as Athenian, Theban. Of place, from the place, as suburban. Verbal nouns are so called because they are born of the verb, as lector. Participial, which sound as participles do, as legens. Verb-like, so called from likeness to the verb, as contemplator; for it is both a verb, of the imperative mood and future tense, and a noun, because it admits comparison. All these species descend from the appellation of nouns. The second part of the noun is comparison. Comparison is so called because from the comparison of one it prefers another. Its degrees are three: positive, comparative and superlative. The positive is so called because it is placed first in the degree of comparison, as doctus. The comparative, because, compared with the positive, it is preferred to it, as doctior; for he knows more than the learned man. The superlative, because it is borne above the comparative, as doctissimus; for he knows more than the more learned. Genders are so called because they generate (generent), as masculine and feminine. The other genders are not genders, but the reckoning and authority of nouns have willed it so. The neuter is so called because it is neither this nor that, that is, neither masculine nor feminine. The common gender is so called because one noun shares in two genders, as hic and haec canis. Contrary to this is the epicene, because it declares both sexes under one gender, as hic piscis. For it is of uncertain sex, which is discerned neither by nature nor by the eyes, but only by skill of sense. “Every gender” is so called because it serves all genders: masculine, feminine, neuter, common and every. Number is so called because by it singular or plural nouns are shown. Figure, because nouns are either simple or compound. Cases are so called from falling (cadendo); for by them inflected nouns are varied and fall. The nominative case is so called because by it we name something, as hic magister. The genitive, because by it we ask the stock (genus) of anyone, as “the son of this master,” or because we signify a thing, as “the book of this master.” The dative, because by it we show that we give something to someone, as “give to this master.” The accusative, because by it we accuse someone, as “I accuse this master.” The vocative, because by it we call someone, as “O master.” The ablative, because by it we signify that we take something away from someone, as “take away from the master.” Hexaptote nouns are so called because they have variations through six cases, as unus. Pentaptote, because they vary only in five cases, as doctus. Tetraptote, because they are declined only in four cases, as lateris. Triptote, only in three, as templum. Diptote, only in two, as Iuppiter. Monoptote, because they use only one case, as frugi.