Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
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Scottish Gaelic seall
Proto-Celtic *sil-n- (inherited)
Irish súil (cognate)
Ancient Greek στίλβω (cognate)
Middle Irish sellaid (inherited)
Old Irish solus (cognate)

Scottish Gaelic muin (link)
Scottish Gaelic ath-sheall (prefix)
Scottish Gaelic dà-sheallach (affix)
Scottish Gaelic trì-sheallach (affix)