meaning of tester
1. A headpiece; a helmet.
2. A flat canopy, as over a pulpit or tomb.
3. A canopy over a bed, supported by the bedposts.
4. An old French silver coin, originally of the value of about eighteen pence, subsequently reduced to ninepence, and later to sixpence, sterling. Hence, in modern English slang, a sixpence; -- often contracted to tizzy. Called also teston.
5. a flat canopy especially one over a four-poster bed