Refinement in argument or speculation; (excessive) use of fine distinctions.

Delicacy, fineness; (also) intricacy, complexity. Cf. subtlety, n. 2 7a.

Judicious selection; the faculty of choosing with taste or nice discrimination. Obsolete.

Subtle or elegant refinement, esp. of speech or thought; discernment; subtlety; delicacy. Also: a refined thought, action, etc.

Delicacy or subtlety of discrimination or interpretation; refinement; refined grace; (also) an instance of this.

Keenness of sensory perception; acuteness or subtlety of observation, discernment, understanding, etc.; perceptiveness. Now somewhat rare.

Fineness or nicety of distinction, esp. that which is difficult to discern or analyse; intricate or (in later use) understated delicacy or…

Critical taste. Obsolete. rare.

The quality or condition of being subtle (in various senses of the adjective); subtlety. Cf. subtileness, n.