Proto-Germanic *þeuraz

→ Danish tyr (inherited)

→ Finnish teuras (borrowed)

→ Faroese tjórur (inherited)

→ Old Swedish þiur (inherited)

→ Icelandic þjór (inherited)

→ Norwegian Bokmål tyr (inherited)

→ Norwegian Nynorsk tyr (derived)

→ Norwegian Nynorsk tjor (inherited)

→ Old Norse þjórr (inherited)

→ Swedish tjur (inherited)