What is "tears of wine"

Tear \Tear\ (t[=e]r), n. [AS. te['a]r; akin to G. z["a]rhe, OHG. zahar, OFries. & Icel. t[=a]r, Sw. t[*a]r, Dan. taare, Goth. tagr, OIr. d[=e]r, W. dagr, OW. dacr, L. lacrima, lacruma, for older dacruma, Gr. da`kry, da`kryon, da`kryma. [root]59. Cf. Lachrymose.]

1. (Physiol.) A drop of the limpid, saline fluid secreted, normally in small amount, by the lachrymal gland, and diffused between the eye and the eyelids to moisten the parts and facilitate their motion. Ordinarily the secretion passes through the lachrymal duct into the nose, but when it is increased by emotion or other causes, it overflows the lids.

   And yet for thee ne wept she never a tear.
   --Chaucer.

2. Something in the form of a transparent drop of fluid matter; also, a solid, transparent, tear-shaped drop, as of some balsams or resins.

   Let Araby extol her happy coast, Her fragrant flowers, her trees with precious tears.
   --Dryden.

3. That which causes or accompanies tears; a lament; a dirge. [R.] ``Some melodous tear.''
   --Milton.

4. (Glass Manuf.) A partially vitrified bit of clay in glass.

   Note: Tear is sometimes used in the formation of self-explaining compounds; as, tear-distilling, tear-drop, tear-filled, tear-stained, and the like.

   Tears of St. Lawrence, the Perseid shower of meteors, seen every year on or about the eve of St. Lawrence, August 9th.

   Tears of wine, drops which form and roll down a glass above the surface of strong wine. The phenomenon is due to the evaporation of alcohol from the surface layer, which, becoming more watery, increases in surface tension and creeps up the sides until its weight causes it to break.

n. a ring of clear liquid, forming into drops, near the top of a glass of fortified wine; the result of differential evaporation of alcohol and subsequent changes in surface tension

The phenomenon called tears of wine is manifested as a ring of clear liquid, near the top of a glass of wine, from which droplets continuously form and drop back into the wine. It is most readily observed in a wine which has a high alcohol content. It is also referred to as wine legs, curtains, or church windows.