Examples:
cartography
card
archaeology
archetype
monarchy
legal
loyal
purse
personal
cinema
kinase
car
carpenter
hippopotamus
Mesopotamia
dative
data
date
...
Icelandic
átján
←
Danish
atten
(cognate)
←
German
achtzehn
(cognate)
←
English
eighteen
(cognate)
←
Proto-Germanic
*ahtōutehun
(derived)
←
Old Norse
átján
(derived)
←
Swedish
arton
(cognate)
→
Westrobothnian
atan
(cognate)
→
Icelandic
einn af átján
(mention)