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P. and V. ἀφανής, ἄδηλος, V. ἄφαντος.
invisible: P. ἀόρατος.
unnoticed: use adv. P. and V. λάθρα.
do a thing unseen, v.: use P. and V. λανθάνειν ποιῶν τι.
unseen by, without the knowledge of: Ar. and V. λάθρα (gen.), P. κρύφα (gen.).