Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Old Irish so-

→ Irish soraidh (affix)
→ Irish sochar (mention)
→ Scottish Gaelic soraidh (affix)
→ Old Irish do- (link)
→ Old Irish soinmech (affix)
→ Old Irish súaichnid (affix)
→ Old Irish sochuide (affix)