113. Some nouns are formed with stems identical with verb stems.
πτύχ-ες (πτύσσω for πτυχι̯ω)
στίχ-ες (στείχω, ἔ-στῐχ-ον)
πτῶκ-α (πτήσσω, ἔ-πτακ-ον)
δῷ for δωμ
cp. δἄ- (dm̥) in δά-πεδον (lit. house floor)
φρίξ, θρίξ, Στύξ
In these nouns the stem is usually either in the weak form or in the O-form (§ 38).
Originally the stem was long (and accented) in the nominative and accusative, weak (with the accent on the case ending) in the genitive and dative. Instances of this variation have been given in § 106; cp. § 114*.
Commonly however a nominal stem is formed from a verb stem by means of one or more suffixes, which we may call nominal suffixes. These are of twο kinds.
- Primary, by which nouns are formed from verb stems; as -ο in ἀγ-ό-ς leader, τί in φά-τι-ς saying. Nouns so formed are called primitive (sometimes verbal; but this term is better known in a more restricted sense, § 84).
- Secondary, by which nοuns are formed from other nοuns; as -ιο in δίκα-ιο-ς just, -ευ in ἰππ-εύ-ς hοrseman. These nouns are called denοminatiνe.
The suffixes which mark the feminine gender might be classified as secondary; thus the stem καλη- might be said to be formed by a fresh suffix from καλο-, the stem δμητειρᾰ- (for δμη-τερ-ι̯ᾰ) from δμη-τερ-, etc. But it is more convenient to treat the feminine endings as mere inflections, along with the corresponding masuline forms.
In the same way we might treat suffixes like -τρο (in ἰη-τρό-ς healer, ἄροτρο-ν plough) as compounded of -τηρ or -τερ (ἰη-τήρ healer, ἀρο-τήρ ploughman), and a secondary -ο. Practically, however, -τρο is a single primary suffix: and this applies also to -μνο (in βέλεμνο-ν dart), which might be resolved into μο + εν + ο, and to many similar cases.