perdu

adj

1. (not-comparable, obsolete)Stationed in an exposed or hazardous position; hidden in ambush. Originally as sentinel perdu.

   “a perdue captain”

2. (archaic, not-comparable)In a dangerous situation; lost, desperate.

   “Among certain grizzled sea-gossips of the gun decks and forecastle went a rumor perdue […]”

3. (archaic, not-comparable)Hidden; concealed from sight. Chiefly with lie.

   “He should lie Perdue who is to walk the round.”

   “I stood perdu behind Mr Grimbold; a tall personage, whose broad shoulders, however, just permitted me to peep over at the Major, who had not yet espied me.”

noun

1. One placed on watch, or in ambush.
2. A soldier sent on a forlorn hope.

   “To watch, poor perdu, / With this thin helm?”