Where does “cóicthiges” come from?

cóicthiges (Old Irish) comes from Old Irish cóic, from Proto-Celtic kʷenkʷe, from Proto-Indo-European pénkʷe — five.

Ancestry of “cóicthiges”, step by step

cóicthiges traces back through two separate lines of ancestry.

via Old Irish cóic

StepLanguageWordMeaning
1Old Irishcóicfive
2Proto-Celtickʷenkʷefive
3Proto-Indo-Europeanpénkʷefive

via Old Irish deich

StepLanguageWordMeaning
1Old Irishdeichten; second-person singular imperative of do·fich
2Proto-Celticdekamten
3Proto-Indo-Europeandéḱm̥ten

Words derived from “cóicthiges”

Every word from Proto-Indo-European pénkʷe →Every word from Proto-Celtic kʷenkʷe →Every word from Old Irish cóic →