Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Welsh
mollt
←
Breton
maout
(cognate)
←
Gaulish
multo
(cognate)
←
Proto-Celtic
*moltos
(inherited)
←
Cornish
mols
(cognate)
←
Old Irish
molt
(cognate)
→
Breton
maout
(cognate)
→
Irish
molt
(cognate)
→
Scottish Gaelic
mult
(cognate)
→
Manx
mohlt
(cognate)
→
Old Irish
molt
(cognate)