Extended Strong's Greek Lexicon (Abbott-Smith based)
be hidden
Usage: λανθάνω [in LXX for עָלַם ni., etc. ;] to escape notice, be hidden (from): Mrk.7:24, Luk.8:47; with accusative of person(s), Act.26:26, 2Pe.3:5 3:8; as in common cl. idiom, before ptcp., ἔλαθον ξενίσαντες, entertained unawares, Heb.13:2 (cf. ἐκ-, ἐπι-λανθάνω).† (AS)