This Proto-Indo-European entry contains reconstructed words and roots. As such, the term(s) in this entry are not directly attested, but are hypothesized to have existed based on comparative evidence.



Given the attested forms in the daughter languages, some have proposed that the original form was *wéḱs (whence Armenian, Old Prussian and possibly Ancient Greek). The initial *s- would then be secondary (imported from *septḿ̥), and when it was just added the result was *swéḱs (Celtic, Iranian, and Ancient Greek if it is not from *wéḱs), whereas when it was substituted for the original consonant, the result was *séḱs (Sanskrit, Latin, Germanic, Lithuanian and OCS).


Proto-Indo-European cardinal numbers
 <  5 6 7  > 
    Cardinal : *swéḱs
    Ordinal : *sweḱstós[1]


  1. six


  • Albanian: *seksti
  • Armenian:
  • Balto-Slavic: *šéš
  • Celtic: *swexs (see there for further descendants)
  • Germanic: *sehs (see there for further descendants)
  • Hellenic: *hwéks
  • Indo-Iranian: *šwáćš (see there for further descendants)
  • Italic: *seks
    • Latin: sex (see there for further descendants)
  • Kartvelian: *eks₁w- (see there for further descendants)
  • Tocharian:

Further readingEdit


  1. ^ Fortson, Benjamin W. (2004, 2010) Indo-European Language and Culture: An Introduction, Oxford: Blackwell