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subtle; delicate; fine
difficult; complex; tricky; delicate (situation, position, etc.); close (e.g. decision)
doubtful; questionable; dicey
not great; iffy
喧嘩の後、二人の関係は微妙なままだった。
Their relationship was delicate.
業界再編をめぐって会社は微妙な立場に置かれている。
Caught up in the industry restructuring, the company is in a tricky position.
訓練を受けると色の微妙な違いが分かる。
I can tell the subtle difference in colors.