Proto-Altaic: *numu ( ~ l-, -i)
Meaning: task, important affair
Russian meaning: задача, важное дело
Comments: It is interesting to note WMong. nom (with a variant lom) '(religious) law, religious book'. It is, of course, a borrowing < OT nom < Sogd. nwm < Gr. nomos, but the variant lom could indicate that there had been an original *lom that merged with the borrowed nom. In that case a reconstruction of *l- for PA would be justified.
