frontage; width (of a building, plot of land, etc.)
breadth (e.g. of one's knowledge); scope (e.g. of one's work); range
この店は間口が狭いが奥行きがある。
This shop has a narrow frontage but is deep.
間口の広い建物が通りに面して建つ。
A building with a wide frontage stands facing the street.
間口が三間ほどの町家が並んでいる。
Townhouses with a frontage of about three ken stand in a row.