Collins Russian Dictionary 2nd Edition © HarperCollins Publishers 2000, 1997:
ambush [ˈæmbuʃ] n заса́да
vt устра́ивать (устро́ить*perf) заса́ду +dat
* is used to mark translations which have irregular inflections. The Russian-English side of the dictionary gives inflectional information.
Русский: