Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Latin
Helvetius
←
Gaulish
-elu
(derived)
←
Gaulish
etu-
(mention)
←
Proto-Celtic
*elu
(derived)
←
Proto-Indo-European
*pelh₁u-
(derived)
←
Old Irish
íath
(cognate)
→
Latin
Helvetia
(mention)
→
Latin
Ricina
(mention)