a town of the hundred of Shropham, in the county of Norfolk, eighty miles from London. It stands on a branch of the river Ouse, and consists of three parishes. It was formerly much more extensive than it is at present, and in the reign of Edward the Third it contained twenty churches, eight monasteries, and six hospitals. Many of the remaining buildings exhibit marks of great antiquity, though the town is not otherwise remarkable. The county assizes are held here once in each year. Thetford is a borough, with a mayor, four aldermen, and eleven councillors, and it returns two members to parliament. There is some little trade by the Ouse with Lynn. The inhabitants amounted in 1821 to 2922, and in 1831 to 3462.