This is the 2468th most frequent Polish word.
estonii
"Estonii" is the genitive or locative form of "Estonia" in Polish, meaning "of Estonia" or "in Estonia."
Here, the word 'Estonii' is used in the locative case to indicate the location where the action took place.
Byłem niedawno w Estonii i podobała mi się tamtejsza atmosfera.
I was recently in Estonia and liked the atmosphere there.
In this case, 'Estonii' is used in the genitive case to denote possession (the history of Estonia).
Historia Estonii jest bardzo interesująca.
The history of Estonia is very interesting.
Here, 'Estonii' is in the genitive case, showing the map's relation (of Estonia).