The unglossed headword occurs in Attic Comedy (e.g. Aristophanes fr. 656 Kock, now 671 K.-A.; Pherecrates fr. 165 Kock, now 175 K.-A.) and elsewhere. LSJ s.v.: "only in phrase poi= k.; which some Gramm. expl. by poi= gh=s; whither away? some by poi= dh/; say whither?". Possibly genitive case, though the attested variant khgxo/s may be composed of the elements kh|= and a)gxo/s.