Etymology Dictionary

AMBUSH,  a hiding in a wood.  (F.,—Low Lat.—Scand.)   In Shakespeare, Meas. for Meas. i. 3. 41.   A corruption of an older embush or enbush, which was originally a verb, signifying 'to set in ambush.'   The corruption from e to a was due to Spanish influence; see Ambuscade.   Rob. of Brunne, in his tr. of P. Langtoft, has enbussement, p. 187, bussement, p. 242; also the pp. enbussed, set in ambush, p. 187, as well as the simple form bussed on the same page.   In all these cases, ss stands for sh, as in Rob. of Gloucester.   Gower has embuisshed, embusshement, C. A. i. 260, iii. 208.—O.F. embuscher, embuissier, to set in ambush.—Low Lat. imboscare, to set in ambush, lit. 'to set in a bush,' still preserved in Ital. imboscare.—Lat. in-, in (which becomes im- before b); and Low Lat. boscus, a bush, wood, thicket, whence O.F. bos, mod. F. bois.   This word is really of Scandinavian origin.   See Bush.   Der. ambush-ment; and see ambuscade.