astragal

thumb|upright=2.0|Astragal architectural element as part of a Doric order column thumb|Diagram of an astragalus profile as part of an Ionic order column

An astragal is a moulding profile composed of a half-round surface surrounded by two flat planes (fillets). An astragal is sometimes referred to as a miniature torus. It can be an architectural element used at the top or base of a column, but is also employed as a framing device on furniture and woodwork.