Words: Venetian mirror
Part of speech: n
Definition: a mirror made via the method of making mirrors out of plate glass invented by 16th-century Venetian glassmakers, who covered the back of the glass with mercury, obtaining near-perfect and undistorted reflection.
Example: For over one hundred years, Venetian mirrors installed in richly decorated frames served as luxury decorations for palaces throughout Europe, but the secret of the mercury process eventually arrived in London and Paris during the 17th century, due to industrial espionage.