Possibly from Proto-Afroasiatic*ka/urVm-; compare Proto-West Chadic *kurVm ("woods"), whence Kanurikulimi(“forest”) and Hausakurmi(“jungle”); as well as Proto-Semitic*karm, whence Hebrewכֶּרֶם(kerem, “vineyard”), Aramaicכַּרְמָא(karmā, “vineyard”), Arabicكَرْم(karm, “vineyard”). However, Peust argues that these Semitic words must be borrowed from Egyptian, as the Egyptian word seems to have originally been kꜣnw before undergoing a sound change that caused the coalescence of the two final consonants into m.
Peust, Carsten (1999) Egyptian Phonology: An Introduction to the Phonology of a Dead Language[2], Göttingen: Peust und Gutschmidt Verlag GbR, page 163
^ Loprieno, Antonio (1995) Ancient Egyptian: A Linguistic Introduction, Cambridge: Cambridge University Press, →ISBN, page 31 (but see also Peust)