What does it mean "Floor of House"  

don’t know exactly the original word in portuguese. If you have the word in Portuguese i can help you.

Without knowing, i can only imagine that it means that is a house with 2 floors and you are renting just one of them. Imagine a house with ground floor and 1st floor, two separate entrances. You are renting or buying just one of them. 
Meaning you may be in a detached house but you will have neigbours sharing the house.

That is very common in Portugal. Usually family houses, parents and children, brothers and sisters, etc, and when one of them move away, they rent the place.

Hope that helps 🙂

@gwritejill - if the Pt word you are translating is chão it refers to the ground floor of a house. Does this help?

So that means it's a house, and the part you get is one floor of the house? The owner, or someone else, lives on the other floor(s)?

One example says, "Andar de Mordia" 

Thank you!

Just to make sure I have all these terms correct: 

Terraced House - no one else lives above or below you, the sides of the houses are connected to the next house. 

Detached House - the house is not connected to another house, but it may be renting one floor or all floors of the house

Floor of House - means you are renting one floor of a house, with owner or renters on the other floors

Flat - an apartment

Duplex - an apartment with two or more stories (floors). There may be apartments above or below you. 

Villa - same as detached house?

Is that right?