Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
...
Proto-Slavic *tъdьnь

→ Belarusian тыдзень (inherited)
→ Czech týden (inherited)
→ Kashubian tidzéń (inherited)
→ Lower Sorbian tyźeń (inherited)
→ Upper Sorbian tydźeń (inherited)
→ Polish tydzień (inherited)
→ Serbo-Croatian tjedan (inherited)
→ Serbo-Croatian tjedan (inherited)
→ Serbo-Croatian teden (inherited)
→ Serbo-Croatian тједан (inherited)
→ Slovak týždeň (inherited)
→ Slovene teden (inherited)
→ Silesian tydźyń (inherited)
→ Silesian tydziyń (inherited)
→ Ukrainian тиждень (inherited)
→ Old Czech týden (inherited)