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P. and V. ἄφρακτος, ἀφύλακτος, P. ἀφρούρητος.
unwatched: P. and V. ἀφύλακτος, P. ἄφρουρος.
exposed, not covered with armour: P. and V. γυμνός; see unarmed.
unwalled: P. ἀτείχιστος.
off one's guard: P. and V. ἀφύλακτος, ἄφρακτος (Thuc.), P. ἀπαράσκευος, ἀπροσδόκητος.