Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Manx
cruinn
←
Proto-Celtic
*krundis
(inherited)
←
Welsh
crwn
(cognate)
←
Old Irish
cruind
(inherited)
→
Manx
co-chruinnaght
(confix)
→
Manx
neuchruinn
(prefix)
→
Manx
meechruinn
(prefix)