Examples: cartography card archaeology archetype monarchy legal loyal purse personal cinema kinase car carpenter hippopotamus Mesopotamia dative data date
...
Polish łokieć
Proto-Indo-European *Heh₃l- (mention)
Proto-Slavic *olkъtь (inherited)

Lower Sorbian łokś (cognate)
Polish łokietek (affix)
Polish łokciowy (affix)
Polish podłokietnik (affix)
Serbo-Croatian lakat (cognate)