subtlety

Etymology

From Middle English sotilte, from Old French sutilté, inherited from Latin subtīlitās, from subtīlis (“subtle”). Equivalent to subtle + -ty. Doublet of subtility.

noun

1. (uncountable) The quality of being subtle.
   1. (of things) The quality of being scarcely noticeable or difficult to discern.
      the subtlety of the Mona Lisa’s smile
      […] he had a lifetime of skill in interpreting his father’s gestures: those bent knees meant that something of great subtlety was about to be revealed. 1964, Saul Bellow, Herzog, New York: Viking, pages 248–249
   2. (of things) The quality of being done in a clever way that is not obvious or not direct; the quality of being carefully thought out.
      the subtlety of a writer’s analysis / of a singer’s phrasing
   3. (of people) The quality of being able to achieve one's aims through clever, delicate or indirect methods.
      With all his usual subtlety, he quietly fixed the problem before anyone else noticed it.
      European women often boss their men too, but with a beguiling subtlety unknown to most American females. 1979, William Styron, chapter 3, in Sophie’s Choice, New York: Random House, page 74
   4. (of people) The quality of being able to notice or understand things that are not obvious.
      his subtilty in thinking and reasoning were profound, 1770, Oliver Goldsmith, The Life of Henry St. John, Lord Viscount Bolingbroke, London: T. Davies, page 7
2. (countable) An instance of being subtle, a subtle thing, especially a subtle argument or distinction.
   The subtleties of this overture are often overlooked.
   1561, William Whittingham et al. (translators), Geneva Bible, Wisdom of Solomon 8.8, […] she [Wisdom] knoweth the subtilties of wordes, and the solutions of darke sentences:
   It is your turn now […] to support your philosophical subtilties against the dictates of plain reason and experience. 1779, David Hume, Dialogues Concerning Natural Religion, Part 10, p. 112
   His body was as insensitive to pain as was his mind to subtleties. 1952, John Steinbeck, East of Eden, London: Heinemann, Part 4, Chapter 36, p. 366
3. (countable, historical) An ornate medieval illusion dish or table decoration, especially when made from one thing but crafted to look like another.
   At the king's coronation feast, several subtleties were served between main courses.
   the seruice […] was sumpteous, with many subtleties, straunge deuises, with seuerall poses, and many deintie dishes. 1548, Edward Hall, “The triumphaunt reigne of Kyng Henry the .VIII.”, in The Union of the Two Noble and Illustre Famelies of Lancastre [and] Yorke, London: Richard Grafton
4. (uncountable, countable, archaic) The quality of being clever in surreptitious or deceitful behaviour; an act or argument that shows this quality.
   When eyther Hare or Deare, or any other chase vseth subtleties to deceyue the houndes, we saye they crosse or double. 1575, George Gascoigne, “Termes generall of the huntesman, in hunting of any chase”, in The Noble Arte of Venerie of Hunting, London: Christopher Barker, page 243
5. (countable, obsolete) A trick that creates a false appearance.
6. (uncountable, obsolete) The property of having a low density or thin consistency.
   1630, Thomas Johnson (translator/editor), A Treatise of the Plague […] Collected out of the workes of […] Ambrose Parey, London, Chapter 11, p. 33, Therefore at Paris where naturally, and also through the aboundance of filth that is about the Citie, the Aire is darke and grosse, the pestilent Infection is lesse fierce and contagious then it is in Prouince, for the subtletie of the Aire stimulates or helps forward the Plague.
   About the Air is to be considered, its Temperature as to Heat, Dryness and Moisture, and the Measures of them, its Weight, Clearness, Refractive Power, its Subtilty or Grosness […] 1692, Robert Boyle, General Heads for the Natural History of a Country Great or Small Drawn Out for the Use of Travellers and Navigators, London: John Tailor and S. Hedford, page 3
7. (uncountable, obsolete) The property of being able to penetrate materials easily.
   Hence we see the amazing Subtlety of this Fire, which pervades Glass as readily as if nothing were in the Way. 1760, John Wesley, The Desideratum; or, Electricity Made Plain and Useful, London, pages 37–38