encubierto
/enkuˈbjeɾto/ · B1 · adj
veiled, hidden
🕵️ en + cubierto = in + covered, so covered over, like covert
Cubierto is the past participle of cubrir, to cover, from Latin cooperire. English covert comes from the same root, by way of Old French. Agente encubierto means undercover agent.