G2990 λανθάνω (lanthánō)

KJV renderings: be hid, be ignorant of, unawares
Strong's definition: to lie hid (literally or figuratively); often used adverbially, unwittingly
Derivation: a prolonged form of a primary verb, which is used only as an alternate in certain tenses;

From James Strong's public-domain dictionaries (G), JSON edition by OpenScriptures (CC-BY-SA). Every dotted-underline word in the text links here.