The Collaborative International Dictionary of English v.0.48:

Tenor \Ten"or\, n. [L., from tenere to hold; hence, properly, a
   holding on in a continued course: cf. F. teneur. See
   Tenable, and cf. Tenor a kind of voice.]
   1. A state of holding on in a continuous course; manner of
      continuity; constant mode; general tendency; course;
      career.
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            Along the cool sequestered vale of life
            They kept the noiseless tenor of their away. --Gray.
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   2. That course of thought which holds on through a discourse;
      the general drift or course of thought; purport; intent;
      meaning; understanding.
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            When it [the bond] is paid according to the tenor.
                                                  --Shak.
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            Does not the whole tenor of the divine law
            positively require humility and meekness to all men?
                                                  --Spart.
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   3. Stamp; character; nature.
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            This success would look like chance, if it were
            perpetual, and always of the same tenor. --Dryden.
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   4. (Law) An exact copy of a writing, set forth in the words
      and figures of it. It differs from purport, which is only
      the substance or general import of the instrument.
      --Bouvier.
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   5. [F. t['e]nor, L. tenor, properly, a holding; -- so called
      because the tenor was the voice which took and held the
      principal part, the plain song, air, or tune, to which the
      other voices supplied a harmony above and below: cf. It.
      tenore.] (Mus.)
      (a) The higher of the two kinds of voices usually
          belonging to adult males; hence, the part in the
          harmony adapted to this voice; the second of the four
          parts in the scale of sounds, reckoning from the base,
          and originally the air, to which the other parts were
          auxillary.
      (b) A person who sings the tenor, or the instrument that
          play it.
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   Old Tenor, New Tenor, Middle Tenor, different
      descriptions of paper money, issued at different periods,
      by the American colonial governments in the last century.
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