lanthanō

Greek has ordinary words for hiding something. This one works from the other end. It does not say that anyone hid anything, only that nobody noticed. So when Mark reports that Jesus went into a house and "could not be hidden," the sentence is really that he could not stay unnoticed. No one had concealed him, and he was not concealing himself; the crowd simply found him out.

Often the person who fails to notice is named outright. Paul tells King Agrippa that none of these events has escaped him, since none of it happened in a corner. Peter urges his readers not to let one fact escape them, and says of his opponents that another fact escapes them because they want it to. That last turn is worth watching: in Greek the overlooking can be a choice and not just an accident.

The word has one more job that English cannot copy directly. Greek can set it alongside a second verb, so that the second verb carries the action and this one supplies "without knowing it." That is what happens in Hebrews 13:2, where some people hosted angels and never realized who their guests were. English has to reach for an adverb: "entertained angels unawares."

Hebrews puts that line right next to a close relative of the word, the verb for forgetting or neglecting (ἐπιλανθάνομαι): do not neglect hospitality, because by it some hosted angels without noticing. The two are worth telling apart. Forgetting is losing hold of what you once knew; this word is never taking hold of it in the first place.