The term 'OLD TOWNHOUSE FEATURE' can be summarized by the crossword solution 'ORIEL', which is a five-letter word. An ORIEL is a type of bay window that projects from the wall of a building, often supported by corbels or brackets. ORIEL windows were popular in the late 19th and early 20th centuries, especially in townhouses. They are often found on the upper floors of buildings, providing additional light and space.