Derivational etymology starting from a verb under the future form. The latter, through dropping of the ending, yields the nominative singular of the lemma. This technique was also used to account for other nouns of similar shape. The etymology reverses in fact the derivational link between παῖς and παίζω: the verb is derived from the noun, not the other way round. This is a reversible etymology, as the correct derivation παῖς → παίζω is also found in our sources (Theognostus, Canones sive De orthographia 856: τὸ παίζω σεσημείωται διὰ τῆς αι διφθόγγου· ἀπὸ γὰρ τοῦ παῖς, παιδίζω, καὶ κατὰ συγκοπὴν παίζω· ὡς καὶ παρὰ τὸ δάνειον, δανειάζω, καὶ ἐν συγκοπῇ δανείζω; Etym. Gudianum, pi, p. 447; Eustathius, Comm. Od. 1, 242 Stallbaum). It is attested in Orion, Etymologicum, pi, p. 138 (Παίζω. παρὰ τὴν παιδὶ δοτικὴν παιδίζω, ὡς ποδὶ ποδίζω, ὑπασπίδια προποδίζων. παιδίζω οὖν συγκοπῇ παίζω. οὐδὲν γὰρ εἰς ζω λῆγον φιλεῖ διφθόγγῳ παραλήγεσθαι, ἢ μόνον τὸ δανείζω· καὶ ὡς δώσω δὼς, σάω σῶς, οὕτω παίσω παῖς): the first part, up to παιδίζω οὖν συγκοπῇ παίζω, goes back to Orion; the second part, from οὐδὲν γὰρ εἰς ζω λῆγον is probably a later addition. The result is a circular derivation: from παιδί (dative) one derives *παιδίζω, which becomes παίζω, and from the future παίσω one derives the nominative παῖς.