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

→ Belarusian пячора (mention)
→ Bulgarian пещера (mention)
→ Old Church Slavonic пещера (mention)
→ Macedonian пештера (mention)
→ Old East Slavic печера (mention)
→ Polish pieczara (mention)
→ Russian пещера (mention)
→ Russian печора (mention)
→ Ukrainian печера (mention)