In architecture, "tambour" has three meanings.
In classical architecture, a is the inverted bell of the Corinthian capital around which are carved acanthus leaves for decoration.
thumb|Corinthian columns from the [[Pantheon, Rome, 114–124 AD]]
The term also applies to the wall of a circular structure, whether on the ground or raised aloft on pendentives and carrying a dome (also known as a tholobate).
thumb|upright=1.2|Dome upon tholobate of the [[Pennsylvania State Capitol, Harrisburg]]
Finally, "tambour" can refer to the drum-shaped segments of a column, which is built up in several courses.
thumb|right|upright=1|Columns of the [[Parliament House, Helsinki|Parliament House in Helsinki, Finland]]