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ἀπευθής, κλωπικός, δαυλός, ἐπίσκιος, ἀφανής, ἀθέατος, ἄφαντος, ἄφραστος, ἀπόθετος, ἀπόκρυφος, κρυφαῖος, κρύφιος, λοχαῖος, ἐποπτικός, λαθραῖος, κρυπτάδιος, μυστηριώδης, σκότιος, σκοτεινός