The Collaborative International Dictionary of English v.0.48:

Tact \Tact\, n. [L. tactus a touching, touch, fr. tangere,
   tactum, to touch: cf. F. tact. See Tangent.]
   1. The sense of touch; feeling.
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            Did you suppose that I could not make myself
            sensible to tact as well as sight?    --Southey.
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            Now, sight is a very refined tact.    --J. Le Conte.
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   2. (Mus.) The stroke in beating time.
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   3. Sensitive mental touch; peculiar skill or faculty; nice
      perception or discernment; ready power of appreciating and
      doing what is required by circumstances.
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            He had formed plans not inferior in grandeur and
            boldness to those of Richelieu, and had carried them
            into effect with a tact and wariness worthy of
            Mazarin.                              --Macaulay.
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            A tact which surpassed the tact of her sex as much
            as the tact of her sex surpassed the tact of ours.
                                                  --Macaulay.
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WordNet (r) 3.0 (2006):

tact
    n 1: consideration in dealing with others and avoiding giving
         offense [syn: tact, tactfulness] [ant: tactlessness]