TEWKSBURY, Mass., town in Middlesex County on the Boston and Maine Railroad, five miles south of Lowell. It has large horticultural interests, a chemical factory and contains the State infirmary. It was founded in 1654 and formed a part of the town of Billerica from which it was taken and incorporated 23 Dec. 1734, being named after the ancient town in Gloucestershire, England, famous for its abbey. Pop. 5,265.