Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Manx
scaan
←
Irish
scáthán
(cognate)
←
Manx
(suffix)
←
Manx
an
(suffix)
←
Old Irish
scáth
(derived)