πόστος

η, ον, ή, όν, ποσσοστος, οι
A. which in the ordinal series? π. δὴ ἔτος ἐστὶν ὅτε ξείνισσας ἐκεῖνον; how many years is it since . .? Od. 24.288; πόστην (sc. γραμμήν, i. e. on the sun-dial) ἥλιος τέτραπται; Ar. Fr. 163; π. ῥύμη; which side-street? which turning? Philippid. 22; κατὰ π. σφόνδυλον; Gal. 8.238; ἐνθυμήθητι π. ἀφ’ Ἡρακλέους ἐγένετο Arr. Epict. 2.18.22; κατανόησον πόστῳ αὐτῶν μέρει πάντες μαχεσάμενοι νενικήκαμεν with what fraction, i.e. with how small a part, X. Cyr. 4.1.16, cf. Jul. Mis. 340b; Ξενοφῶν π. μέρος τοῦ λόχου ἡ ἐνωμοτία ἐστὶν οὐ διασαφεῖ Arr. Tact. 6.3.
II. ποστός, ή, όν, holding a certain place in the ordinal series, τῇ ποστῇ (sc. ἡμέρᾳ) on such-and-such a day of the month, PMag.Leid.W. 3.35, cf. S.E. M. 5.37. (Prob.from ποσσοστος, formed from πός(ς)οι on analogy of πολλοστός from πολλοί.)
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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