What is "mirror plate"

Mirror \Mir"ror\, n. [OE. mirour, F. miroir, OF. also mireor, fr. (assumed) LL. miratorium, fr. mirare to look at, L. mirari to wonder. See Marvel, and cf. Miracle, Mirador.]

1. A looking-glass or a speculum; any glass or polished substance that forms images by the reflection of rays of light.

   And in her hand she held a mirror bright, Wherein her face she often view[`e]d fair.
   --Spenser.

2. That which gives a true representation, or in which a true image may be seen; hence, a pattern; an exemplar.

   She is mirour of all courtesy.
   --Chaucer.

   O goddess, heavenly bright, Mirror of grace and majesty divine.
   --Spenser.

3. (Zo["o]l.) See Speculum. Mirror carp (Zo["o]l.), a domesticated variety of the carp, having only three or fur rows of very large scales side. Mirror plate.

   1. A flat glass mirror without a frame.

   2. Flat glass used for making mirrors.

      Mirror writing, a manner or form of backward writing, making manuscript resembling in slant and order of letters the reflection of ordinary writing in a mirror. The substitution of this manner of writing for the common manner is a symptom of some kinds of nervous disease.