So delicate or precise as to be difficult to analyze or describe. The artist's use of color was so subtle that it created a sense of depth and emotion in the painting.
Making use of clever and indirect methods to achieve something. She used a subtle approach to persuade her boss to consider her proposal.
Not obvious; elusive or ambiguous. There was a subtle change in his tone that suggested he was not pleased with the decision.
The detective admired the criminal's subtle plan, even as he worked to unravel it.
Possessing or showing keen insight and perception; refined or delicate in understanding or analysis. His subtle mind quickly detected the flaws in the argument.