1.Thin; not dense or gross; rare; as, subtile air; subtile vapor; a subtile medium.
2.Delicately constituted or constructed; nice; fine; delicate; tenuous; finely woven. "A sotil (subtile) twine's thread." "More subtile web Arachne can not spin." "I do distinguish plain Each subtile line of her immortal face."
3.Acute; piercing; searching. "The slow disease and subtile pain."
4.Characterized by nicety of discrimination; discerning; delicate; refined; subtle. (In this sense now commonly written subtle) "The genius of the Spanish people is exquisitely subtile, without being at all acute; hence there is so much humor and so little wit in their literature. The genius of the Italians, on the contrary, is acute, profound, and sensual, but not subtile; hence what they think to be humorous, is merely witty." "The subtile influence of an intellect like Emerson's."
5.Sly; artful; cunning; crafty; subtle; as, a subtile person; a subtile adversary; a subtile scheme. (In this sense now commonly written subtle)
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