Collins Russian Dictionary 2nd Edition © HarperCollins Publishers 2000, 1997:
slaughter [ˈslɔːtər] n (of animals) убо́й; (of people) резня́
vt (animals) забива́ть (заби́ть*perf) (people) ре́зать*(impf)
* is used to mark translations which have irregular inflections. The Russian-English side of the dictionary gives inflectional information.
Русский: