What does ambush mean?
The definition of ambush
Am”bush, n.
Etym: [F. embûche, 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. Heaven, whose high walls fear no assault or siege Or ambush from the deep. Milton.
2 A concealed station, where troops or enemies lie in wait to attack by surprise. Bold in close ambush, base in open field. Dryden.
3 The troops posted in a concealed place, for attacking by surprise; liers in wait. [Obs.] The ambush arose quickly out of their place. Josh. viii. 19. To lay an ambush, to post a force in ambush.

Am”bush, v. t.
[imp. & p. p. Ambushed; p. pr. & vb. n. Ambushing.]
Etym: [OE. enbussen, enbushen, OF. embushier, embuissier, F. embûcher, embusquer, fr. LL. imboscare; in + LL. boscus, buscus, a wood; akin to G. bush, E. bush. See Ambuscade, Bu.]

1 To station in ambush with a view to surprise an enemy. By ambushed men behind their temple Dryden.
2 To attack by ambush; to waylay.

Am”bush, v. i.
To lie in wait, for the purpose of attacking by surprise; to lurk. Nor saw the snake that ambushed for his prey. Trumbull.