The Collaborative International Dictionary of English v.0.48:

Ambush \Am"bush\ ([a^]m"b[oo^]sh), v. t. [imp. & p. p.
   Ambushed ([a^]m"b[oo^]shd); p. pr. & vb. n. Ambushing.]
   [OE. enbussen, enbushen, OF. embushier, embuissier, F.
   emb[^u]cher, embusquer, fr. LL. imboscare; in + LL. boscus,
   buscus, a wood; akin to G. bush, E. bush. See Ambuscade,
   Bush.]
   1. To station in ambush with a view to surprise an enemy.
      [1913 Webster]

            By ambushed men behind their temple laid,
            We have the king of Mexico betrayed.  --Dryden.
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   2. To attack by ambush; to waylay.
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The Collaborative International Dictionary of English v.0.48:

Ambush \Am"bush\, v. i.
   To lie in wait, for the purpose of attacking by surprise; to
   lurk.
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         Nor saw the snake that ambushed for his prey.
                                                  --Trumbull.
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The Collaborative International Dictionary of English v.0.48:

Ambush \Am"bush\ ([a^]m"b[oo^]sh), n. [F. emb[^u]che, fr. the
   verb. See Ambush, v. t.]
   1. A disposition or arrangement of troops for attacking an
      enemy unexpectedly from a concealed station. Hence: Unseen
      peril; a device to entrap; a snare.
      [1913 Webster]

            Heaven, whose high walls fear no assault or siege
            Or ambush from the deep.              --Milton.
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   2. A concealed station, where troops or enemies lie in wait
      to attack by surprise.
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            Bold in close ambush, base in open field. --Dryden.
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   3. The troops posted in a concealed place, for attacking by
      surprise; liers in wait. [Obs.]
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            The ambush arose quickly out of their place. --Josh.
                                                  viii. 19.
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   To lay an ambush, to post a force in ambush.
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WordNet (r) 3.0 (2006):

ambush
    n 1: the act of concealing yourself and lying in wait to attack
         by surprise [syn: ambush, ambuscade, lying in wait,
         trap]
    v 1: wait in hiding to attack [syn: ambush, scupper,
         bushwhack, waylay, lurk, ambuscade, lie in wait]
    2: hunt (quarry) by stalking and ambushing [syn: still-hunt,
       ambush]

The Free On-line Dictionary of Computing (19 January 2023):

AMBUSH

    A language for linear programming problems in a
   materials processing and transportation network.

   ["AMBUSH - An Advanced Model Builder for Linear Programming",
   T.R. White et al, National Petroleum Refiners Assoc Comp Conf
   (Nov 1971)].

   (1995-06-19)