from
The Collaborative International Dictionary of English v.0.48
Subtilty \Sub"til*ty\, n. [Contr. fr. subtility.]
1. The quality or state of being subtile; thinness; fineness;
as, the subtility of air or light.
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2. Refinement; extreme acuteness; subtlety.
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Intelligible discourses are spoiled by too much
subtility in nice divisions. --Locke.
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3. Cunning; skill; craft. [Obs.]
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To learn a lewd man this subtility. --Chaucer.
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4. Slyness in design; artifice; guile; a cunning design or
artifice; a trick; subtlety.
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O full of all subtility and all mischief. --Acts
xiii. 10.
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Note: In senses 2, 3, and 4 the word is more commonly written
subtlety.
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