Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Welsh
crwn
←
Proto-Celtic
*krundis
(inherited)
←
Old Irish
cruinn
(cognate)
→
Welsh
hirgrwn
(compound)
→
Irish
cruinn
(cognate)
→
Scottish Gaelic
cruinn
(cognate)
→
Manx
cruinn
(cognate)