Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Scottish Gaelic
ma
←
Breton
mar
(cognate)
←
Proto-Celtic
*mā
(inherited)
←
Proto-Celtic
*ma
(mention)
←
Proto-Indo-European
*meh₂
(inherited)
←
Cornish
-
(cognate)
←
Old Irish
má
(inherited)
→
Scottish Gaelic
nan
(link)