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

→ English Lugh (derived)
→ English Carlisle (compound)
→ Welsh Llywelyn (inherited)
→ Irish Lugh (inherited)
→ Irish Lughaidh (compound)
→ Latin Lugdunum (cognate)
→ Primitive Irish ᚂᚒᚌ (inherited)
→ Old Irish Lug (inherited)
→ Old Irish Lugaid (compound)