What is a canopy over a bed, supported by the bedposts. No testers to the bed, and the saddles and portmanteaus heaped on me to keep off the cold. Walpole called?

tester — A canopy over a bed, supported by the bedposts. No testers to the bed, and the saddles and portmanteaus heaped on me to keep off the cold. Walpole. (Webster's 1913.)