Here in Venezuela that word means the owner and it can pertain to the owner of a car the owner of a phone etc it can certainly mean landlord but it's like saying tuna when you mean fish. A tuna is a fish, but there are many other fishes. One can be the dueño of something without being a landlord.
The legal definition aside (since not all of us are becoming lawyers), "landlord" (in American English anyway) can be the person who rents out the property and not necessarily the owner. When renting a house in Austin, we refered to the person we gave money to who was someone in the retail firm hired by the owner as the landlord even though we knew the owner. I don't think we ever refered to the owner as the landlord (just as the owner) while we were there although it probably wouldn't have sounded weird.