per·du /ˈpɝ(ˌ)du, (ˌ)dju; (ˌ)pɚ/
  (a.)隱藏的;看不見的;埋伏的
  Per·du n.
  1. One placed on watch, or in ambush.
  2. A soldier sent on a forlorn hope.
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  Per·du, Per·due  a.
  1. Lost to view; in concealment or ambush.
     He should lie perdue who is to walk the round.   --Fuller.
  2. Accustomed to, or employed in, desperate enterprises; hence, reckless; hopeless. “A perdue captain.”
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