subtlety

noun11

1. •
   The quality of being subtle.
2. •
   An instance of being subtle, a subtle thing, especially a subtle argument or distinction.

   • The subtleties of this overture are often overlooked.
3. •
   The quality of being scarcely noticeable or difficult to discern. (of things)

   • [H]e 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
4. •
   The quality of being done in a clever way that is not obvious or not direct; the quality of being carefully thought out. (of things)

   • Something kinda sad about / The way that things have come to be / Desensitized to everything / What became of subtlety? / How can this mean anything to me / If I really don't feel anything at all? — 1996
5. •
   The quality of being able to achieve one's aims through clever, delicate or indirect methods. (of people)

   • With all his usual subtlety, he quietly fixed the problem before anyone else noticed it.
6. •
   The quality of being able to notice or understand things that are not obvious. (of people)

   • To give subtilty to the simple, to the young man knowledge and discretion. — 1611
7. •
   (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.
8. •
   (no longer used) 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
9. •
   (no longer used) A trick that creates a false appearance.

   • You doe yet taste / Some subtleties o’ th’ Isle, that will not let you / Beleeue things certaine: — 1610
10. •
    (no longer used) The property of having a low density or thin consistency.

    • 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
11. •
    (no longer used) 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