Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Irish
áth
←
Proto-Celtic
*yātus
(inherited)
←
Proto-Indo-European
*yeh₂-
(root)
←
Proto-Indo-European
*yeh₂-
(derived)
←
Old Irish
áth
(inherited)
→
English
Athy
(mention)
→
Irish
áthán
(affix)
→
Scottish Gaelic
àth
(cognate)
→
Manx
aah
(cognate)