A convex moulding having an outline of a quarter-circle, an ovolo or echinus; also attributive, as "quarter round moulding", "quarter round tool", etc.
Origin
Mid 17th century; earliest use found in John Evelyn (1620–1706), diarist and writer.
Definition of quarter-round in US English:
quarter-round
noun
Architecture
A convex moulding having an outline of a quarter-circle, an ovolo or echinus; also attributive, as "quarter round moulding", "quarter round tool", etc.
Origin
Mid 17th century; earliest use found in John Evelyn (1620–1706), diarist and writer.