n. [spectacles] designed to "pinch the nose" (as the term [literally] means in [French]), as opposed to [eyeglass]es held on by sidepieces going over the ears, or [lorgnette|opera glasses], which use a handle. The [plural] is spelt the same, but pronounced with an 's' on the end.*

The pince-nez was made possible by the invention of the steel spring in the mid-19th century. They were unstable and eventually incorporated a cord or ribbon attached on one side to prevent them falling off and shattering, rather like a [monocle]. Later versions allowed the folding of one lens over the other, for [compactness]' sake.

The glasses played a central role in Sir [Arthur Conan Doyle]'s short story "The Adventure of the Golden Pince-Nez" published in the 1905 collection "The Return of [Sherlock Holmes]."

* The words '[corps],' '[rendezvous], '[faux-pas]' and '[chassis]' do the same.
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Pince-nez (thing)