Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Scottish Gaelic
eigh
←
Welsh
iâ
(cognate)
←
Irish
oighear
(cognate)
←
Cornish
yey
(cognate)
←
Old Irish
aig
(inherited)
→
Scottish Gaelic
eigh-bheinn
(compound)
→
Scottish Gaelic
eigh-shruth
(compound)
→
Cornish
yey
(cognate)