smoke ring

smoke ring (plural smoke rings)

1. A ring of smoke exhaled by a smoker.
   • 1854, John Ross Dix, The Worth of the Worthless, Boston: Shakspeare Division of Sons of Temperance, Chapter 2, p. 46,

     Puff—puff—puff—went John’s pipe; and as the circling smoke-rings went up, the pictures therein framed became as distinct as if they had been drawn by the delicate pencil of Hammatt Billings.

   • 1891, Arthur Conan Doyle, “The Five Orange Pips” in The Adventures of Sherlock Holmes, 1892,

     Then he lit his pipe, and leaning back in his chair he watched the blue smoke-rings as they chased each other up to the ceiling.

   • 1937, J. R. R. Tolkien, The Hobbit, New York: Ballantine, 1982, Chapter 1, p. 13,

     He was blowing the most enormous smoke-rings, and wherever he told one to go, it went—up the chimney, or behind the clock on the mantelpiece, or under the table, or round and round the ceiling; but wherever it went it was not quick enough to escape Gandalf. Pop! he sent a smaller smoke-ring from his short clay-pipe straight through each one of Thorin’s.

   • 2013 March 1, Frank Fish, George Lauder, “Not Just Going with the Flow”, in American Scientist‎, volume 101, number 2, page 114:

     An extreme version of vorticity is a vortex. The vortex is a spinning, cyclonic mass of fluid, which can be observed in the rotation of water going down a drain, as well as in smoke rings, tornados and hurricanes.

   A smoke ring persists for a surprisingly long time, illustrating the slow rate at which viscosity dissipates the energy of a vortex.