which neither hinders nor causes the formation of a single significant sound or phrase out of several sounds, and which, if the phrase stands by itself, cannot properly stand at the beginning of it, e.g. μέν, δή, τοί, δέ; or else it is a sound without meaning capable of forming one significant sound or phrase out of several sounds having each a meaning of their own, e.g. ἀμφί, περί.
A joint is a sound without meaning which marks the beginning or end of a phrase or a division in it, and naturally stands at either end or in the middle. [Note]
A noun is a composite sound with a meaning, not indicative of time, no part of which has a meaning by itself; for in compounds we do not use each part as having a meaning of its own, for instance, in "Theodorus," there is no meaning of δῶρον (gift).
A verb is a composite sound with a meaning, indicative of time, no part of which has a meaning by itself—just as in nouns. "Man" or "white" does not signify time, but "walks" and "has walked" connote present and past time respectively.
A case(or inflection)of a noun or verb is that which signifies either "of" or "to" a thing and the like;