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"Finca" is a form of "finca", a noun which is often translated as "property". "Estancia" is a noun which is often translated as "stay". Learn more about the difference between "estancia" and "finca" below.
la estancia(
ehs
-
tahn
-
syah
)A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).
2. (large room)
a. room 
La sala de su casa es una estancia impresionante.The living room of their house is an impressive room.
3. (farm) (Latin America)
Regionalism used in Latin America: all the countries in South America, Central America, and the Caribbean. Does not include Spain.
a. cattle ranch 
Siempre visitábamos la estancia de mis abuelos.We always used to visit my grandparents' cattle ranch.
4. (property, land) (Caribbean)
Regionalism used in the Caribbean: Cuba, the Dominican Republic, and Puerto Rico
a. country estate 
Su familia tiene una estancia bonita en Santo Domingo.His family has a beautiful country estate in Santo Domingo.
la finca(
feeng
-
kah
)A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).
a. property 
Tengo un par de fincas en venta en un pueblo a diez kilómetros de aquí.I have a couple of properties for sale in a town ten kilometers away from here.
b. country house 
Todos los fines de semana, mis suegros se van a su finca en el norte de la región.Every weekend, my in-laws go to their country house in the north.
c. country estate 
Nuestro vecino nos invitó a su finca a montar a caballo.Our neighbor invited us to his country estate to go riding.
d. ranch  (United States)
Regionalism used in the United States
La finca tiene una vista espectacular a las montañas.The ranch has a spectacular view of the mountains.
e. farm 
Me compré una finca en el campo para irme allí a vivir cuando me jubile.I bought a farm in the countryside to move to when I retire.
a. building 
Se vende piso en finca clásica con bonita fachada y balcones.Apartment for sale in a classic-style building with an attractive facade and balconies.