give or hand over as a pledge:—Med., have a thing pledged to one, accept as a surety, δειλαί τοι δειλῶν γε καὶ ἐγγύαι ἐγγυάασθαι Od. 8.351 (nowhere else in Hom.).
esp. of a father, plight, betroth, θυγατέρα ἐγγυᾶν τινι Hdt. 6.57 (v. infr.); Ζεὺς ἠγγύησε καὶ δίδωςʼ E. IA 703:—Med., have a woman plighted or betrothed to one, c. acc., D. 57.41:—Act. and Med. opposed, Hdt. 6.130:—Pass., of the man, to be betrothed, θυγατρί τινος Pl. Lg. 923d.
Med., pledge oneself, give security, ἐγγύας ἐγγυησάμενοι πρὸς τὸ δημόσιον And. 1.73, cf. Pl. Lg. 953e; ἐπί τισι Lys. 23.9; ἐ. τινὶ ὅτι . . Pl. Euthd. 274b.
c. acc. et inf. fut., promise or engage that . . , Pi. O. 11(10).16, Ar. Pl. 1202, X. An. 7.4.13, Pl. Prt. 336d, etc.; ἐγγυᾶσθαί [τινα] καὶ ὁμολογεῖν παρέξειν Lys. 13.23; ἐγγυωμένη δώσειν Babr. 58.10.
c. acc. rei, answer for, ἐγγυᾶσθαι τὰ μέλλοντʼ ἔσεσθαι D. 18.191: c. acc. pers., Pl. Lg. 855b; ἐγγυᾶσθαί τινά τινι give surety for him to another, D. 33.28; ἐγγύην ἐγγυᾶσθαί τινα πρός τινα Pl. Phd. 115d; ἐ. τὰ μετέωρα give guarantees without security, SIG 364.46 (Ephesus, iii B.C.).