φυλακή, -ῆς, ἡ
(< φυλάσσω) [in LXX chiefly for מִשְׁמֶרֶת and cogn. forms, also for כֶּלֶא etc.;]
(a) actively, a guarding, guard, watch (Hom., Plat., Xen., al.): cogn. acc., φυλάσσειν φυλακάς, to keep watch, Lk 2:8;
(b) of those who keep watch (as also Lat. custodia), a guard; pl., sentinels, a guard (Hom., al.): Ac 12:10;
(c) of the place where persons are kept under guard, a prison (Hdt., Thuc., al.): Mt 14:10, Mk 6:17, Lk 3:20, Ac 5:19, II Co 6:5, I Pe 3:19, Re 18:2, al.;
(d) of the time during which guard was kept by night (Lat. vigilia; Anthol.), a watch: Mt 14:2524:43, Mk 6:48, Lk 12:38