Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Ukrainian
раціональний
←
Belarusian
рацыяна́льны
(cognate)
←
Latin
ratiōnālis
(borrowed)
←
Polish
racjonalny
(cognate)
←
Russian
рациона́льный
(cognate)