The Collaborative International Dictionary of English v.0.48:

Sincere \Sin*cere"\, a. [Compar. Sincerer; superl.
   Sincerest.] [L. sincerus, of uncertain origin; the first
   part perhaps akin to sin- in singuli (see Single), and the
   second to cernere to separate (cf. Discern): cf. F.
   sinc[`e]re.]
   1. Pure; unmixed; unadulterated.
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            There is no sincere acid in any animal juice.
                                                  --Arbuthnot.
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            A joy which never was sincere till now. --Dryden.
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   2. Whole; perfect; unhurt; uninjured. [Obs.]
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            The inviolable body stood sincere.    --Dryden.
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   3. Being in reality what it appears to be; having a character
      which corresponds with the appearance; not falsely
      assumed; genuine; true; real; as, a sincere desire for
      knowledge; a sincere contempt for meanness.
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            A sincere intention of pleasing God in all our
            actions.                              --Law.
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   4. Honest; free from hypocrisy or dissimulation; as, a
      sincere friend; a sincere person.
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            The more sincere you are, the better it will fare
            with you at the great day of account. --Waterland.
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   Syn: Honest; unfeigned; unvarnished; real; true; unaffected;
        inartificial; frank; upright. See Hearty.
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