Enedron (ἔνεδρον) is the noun form meaning an ambush or a place of lurking — where enemies wait in concealment to attack. It appears in Acts 23:16 describing the Jewish plot against Paul ('heard of their lying in wait [enedron]') and Acts 25:3 where the high priests and chief men asked Festus to transfer Paul to Jerusalem, 'laying an ambush [enedron] to kill him on the way.' The word is purely military in background — the ambush as tactical deception.
The two uses of enedron in Acts bracket Paul's Roman custody period. The first plot (Acts 23) was foiled by Paul's nephew; the second (Acts 25) was circumvented by Paul's appeal to Caesar. In both cases, human conspiracies designed to ambush God's apostle were defeated by God's sovereign management of events — a nephew's overheard conversation, a Roman governor's procedural caution. The enedron plots against Paul fulfilled Jesus's prediction that his disciples would be handed over to councils and stand before governors (Matthew 10:17-18) — and be preserved through it.