From Middle Persian [Book Pahlavi needed] (PWN /⁠pad⁠/, “to, at, in, on”) + Middle Persian [Book Pahlavi needed] (nyhʾn' /⁠nihān⁠/, “concealment, secrecy”). originally a contraction of elements equivalent to New Persian به (be, “in”) + نهان (nehân, “hiding”), i.e. "in hiding".