A.“πταίσω” D.2.20: aor. “ἔπταισα” Hdt.9.101, etc.: pf. “ἔπταικα” Men.675, Bato 1, Plb.3.48.4, (προσ-) Isoc.6.82:— Pass., v. infr.1:
I. trans., cause to stumble or fall, “σύνθεσιν ποτὶ ψεύδει” Pi.Fr.205, cf.LXX 1 Ki.4.3:—Pass., to be missed, of things, Ael. NA2.15; τὰ πταισθέντα failures, errors, Luc.Demon.7; ἃ ἐπταίσθη his failures, Plu.Comp.Dion.Brut.3.
II. intr., stumble, trip, fall, π. πρός τινι stumble against, fall over, “π., ὥσπερ πρὸς ἕρματι, πρὸς τῇ πόλει” Pl.R.553b, cf. A.Pr.926, Theoc.7.26; πρὸς τὰς πέτρας cj. in X. An.4.2.3; prov., “μὴ δὶς πρὸς τὸν αὐτὸν λίθον πταίειν” Plb.31.11.5; also π. περί τινι, μὴ περὶ Μαρδονίῳ πταίσῃ ἡ Ἑλλάς lest Hellas should get a fall over him, i.e. be defeated by him, Hdt.9.101.
2. metaph., make a false step or mistake, Th.2.43, D.2.20, Men.672, etc.; ἐὰν πταίωσί τι when they make a blunder, of medical men, Philem.75.5; οὐκ ἐλάττω, ἐλάχιστα, τὰ πλείω π., Th.1.122, 4.18, 6.33; “ἔν τισι” D. 18.286; “λογισμοῖς” Men.380; τῇ μάχῃ, τοῖς ὅλοις, τοῖς πράγμασι, etc., Plb.18.14.13, 3.48.4, 1.10.1, etc.; “ἀψευδὴς ὢν καὶ μὴ π. τῇ διανοίᾳ περὶ τὰ ὄντα” Pl.Tht.160d; also “π. ὑπ᾽ ἀνάγκας” S.Ph.215 (lyr.); “ὑπό τινος π. τῇ πατρίδι” Plb.5.93.2; “ἐκ τύχης” Id.2.7.3.
