δεῖ (dei)

there is need

—Impers. from δέω (A), there is need (the sense of moral obligation, prop. belonging to χρή, is later, S. Ph. 583, etc.):

I it is needful for, one must, need, there is need of

c. acc. pers. et inf., it is needful for one to do, one must, once in Hom., τί δὲ δεῖ πολεμιζέμεναι . . Ἀργείους why need the Argives fight? Il. 9.337; δ. <μʼ> ἐλθεῖν Pi. O. 6.28, etc.: with nom. of the Pron., ἡγούμην . . δεῖν . . μεγαλοψυχότερος φαίνεσθαι D. 19.235: rarely δεῖ σʼ ὅπως δείξεις, = δεῖ σε δεῖξαι, S. Aj. 556, cf. Ph. 54; δεῖ σʼ ὅπως μηδὲν διοίσεις Cratin. 108; (the full constr. in S. Ph. 77 τοῦτο δεῖ σοφισθῆναι . . ὅπως γενήσῃ): rarely c. dat. pers., there is need of . . for . ., θ

2 it was fated, was doomed

c. acc. rei et inf., δεῖ τι γενέσθαι Th. 5.26; παραδείγματα, καθʼ ἃ δέοι ἀποκρίνεσθαι Pl. Men. 79a, etc.; also ἐπεὶ δέ οἱ ἔδεε κακῶς γενέσθαι since it was fated for him . ., since he was doomed . ., Hdt. 2.161, cf. 8.53, 9.109, S. OT 825; for οἴομαι δεῖν, v. οἴομαι.

abs. with inf. understood, μὴ πεῖθʼ ἃ μὴ δεῖ (sc. πείθειν) S. OC 1442, cf. OT 1273; εἴ τι δέοι, ἤν τι δέῃ (sc. γενέσθαι), X. Mem. 1.2.59, Th. 1.44; κἂν δέῃ (sc. τροχάζειν), τροχάζω Philetaer. 3.

II there is need of

c. gen. rei, there is need of, freq. with neg., οὐδὲν ἂν δέοι πολλοῦ ἀργυρίου Pl. Cri. 45a, etc.; τί δεῖ τῆς ἀρετῆς; Arist. Pol. 1309b10; sts. with inf. added, μακροῦ λόγου δεῖ ταῦτʼ ἐπεξελθεῖν A. Pr. 870, cf. 875, Supp. 407.

b there wants much, far from it, there wants little, all but, there was, to travel

freq. in phrases, πολλοῦ δεῖ there wants much, far from it, ὀλίγου δεῖ there wants little, all but; in full c. inf., πολλοῦ δεῖ οὕτως ἔχειν Pl. Ap. 35d; τοὺς Πλαταιέας ἐλαχίστου ἐδέησε διαφθεῖραι [τὸ πῦρ] Th. 2.77; πολλοῦ γε δεῖ, πολλοῦ γε καὶ δεῖ Ar. Ach. 543, D. 18.300, 21.71; τοῦ πλεῦνος αἰεὶ ἔδεε there was always further to travel, Hdt. 4.43; τοῦ παντὸς δεῖ Luc. Merc.Cond. 13: also ὀλίγου δεῖν abs., in same sense, Pl. Ap. 22a, etc.; μικροῦ δεῖν D. 27.29.

with dat. pers. added, δεῖ μοί τινος A. Ag. 848, E. Med. 565, Th. 1.71, etc.

with acc. pers. added, αὐτὸν γάρ σε δεῖ προμηθέως A. Pr. 86, cf. E. Rh. 837, Hipp. 23.

4 is needful

rarely with Subj. in nom., δεῖ μοί τι something is needful to me, ἓν δεῖ μόνον μοι E. Supp. 594; εἴ τι δέοι τῷ χορῷ Antipho 6.12; πρῶτον μὲν τοῦτο δεῖ, ὑπειληφέναι . . D. 10.15.

III there is need

Med., δεῖται there is need, c. gen., δεῖταί σοι τῆς αὐτῆς ἐρωτήσεως Pl. Men. 79c; ὅσων δέοιτο Aen.Tact. 13.1; ἑτέρου δεῖσθαι στρατηγοῦ νομίζων Plu. Pel. 26: c. inf., ὥστε βραχέʼ ἐμοὶ δεῖσθαι φράσαι S. OC 570 (codd.); δεήσεται . . ἀναγράφεσθαι Aen.Tact. 31.9; τήν μευ γλῶσσαν ἐκτεμεῖν δεῖται Herod. 6.41.

IV it being needful, fitting, though he ought to have done so, there being, need

neut. part. δέον( δεῖν is dub. in Ar. Fr. 220, Lys. 14.7, cf. A.D. Adv. 132.30, Hdn.Gr. 2.328, al., Hsch.): abs., it being needful or fitting, Pl. Prt. 355d, etc.; οὐκ ἀπήντα, δέον, he did not appear in court, though he ought to have done so, D. 21.90: c. inf., Ar. Nu. 988; οὐδὲν δέον there being no need, Hdt. 3.65, etc.: fut. ὡς αὐτίκα δεῆσον διώκειν X. Cyr. 3.2.8: aor. δεῆσαν Plu. Fab. 9, etc.: also δέον ἂν εἴη, = δέοι ἄν, Plb. 2.37.5, etc.: less freq. gen. abs. δέοντος, c. acc. inf., Corn. ND

Subst. δέον, τό (v. sub voc.).

δεῖ

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