TESTER

noun a headpiece; a helmet.

2. tester ·noun a flat canopy, as over a pulpit or tomb.

3. tester ·noun a canopy over a bed, supported by the bedposts.

4. tester ·noun 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.