←
Old English siex (cognate)
←
Old Church Slavonic шесть (cognate)
←
Proto-Indo-Iranian *šwáćš (inherited)
←
Proto-Indo-European *swéḱs (inherited)
←
Proto-Iranian *xšwáš (inherited)
←
Northern Kurdish şeş (cognate)
←
Lithuanian šešì (cognate)
←
Tocharian B ṣkas (cognate)
→
Northern Kurdish şeş (cognate)