River Avon n 1: a river in southwestern England rising in Gloucestershire and flowing through Bristol to empty into the estuary of the Severn [syn: {Avon}, {River Avon}] 2: a river in central England that flows through Stratford-on- Avon and empties into the Severn [syn: {Avon}, {River Avon}, {Upper Avon}, {Upper Avon River}]