Merriam-Webster Collegiate Dictionary - avon

 I. biographical name Earl of — see Anthony Eden  II. geographical name  1. river 96 miles (154 kilometers) central England rising in Northamptonshire & flowing WSW past Stratford-upon-~ into Severn River at Tewkesbury  2. river 65 miles (105 kilometers) S England rising near Devizes in Wiltshire & flowing S into English Channel  3. river 75 miles (121 kilometers) SW England rising in Gloucestershire & flowing S & W through city of Bristol into Bristol Channel at ~mouth  4. — see swan