κλείς, -δός Att.. accusative, κλεῖν, later -εῖδα, pl., κλεῖδες, -ας, contr., -εῖς, ἡ,
[in LXX for מַפְתֵּחַ, Isa.22:22, al. ;]
a key. Fig., τ. βασιλείας τ. οὐρανῶν, Mat.16:19; τ. γνώσεως, Luk.11:52; of David (cf. LXX, l.with), Rev.3:7; τ. θανάτου κ. τ. ᾅδου, Rev.1:18; τ. ἀβύσσαυ, Rev.20:1; τ. φρέατος τῆς ἀ., Rev.9:1.†
(AS)