This is the 724th most frequent Italian word.
fianco
"Fianco" means "side" or "flank" in English.
In this sentence, 'fianco' denotes proximity or adjacency in a physical sense.
Siamo seduti fianco a fianco.
We are sitting side by side.
Here, 'fianco' refers to a part of the body, specifically the side or flank of the torso.
Ho un dolore al fianco sinistro.
I have a pain in my left side.
In this use, 'fianchi' is the plural form and describes the flanks or sides of a hill, indicating the lateral aspects.