[1] : The Collaborative International Dictionary of English v.0.48

sincere \sincere"\, 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`ere.
   1. pure; unmixed; unadulterated.
      1913 webster

            there is no sincere acid in any animal juice.
                                                  --arbuthnot.
      1913 webster

            a joy which never was sincere till now. --dryden.
      1913 webster

   2. whole; perfect; unhurt; uninjured. obs.
      1913 webster

            the inviolable body stood sincere.    --dryden.
      1913 webster

   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.
      1913 webster

            a sincere intention of pleasing god in all our
            actions.                              --law.
      1913 webster

   4. honest; free from hypocrisy or dissimulation; as, a
      sincere friend; a sincere person.
      1913 webster

            the more sincere you are, the better it will fare
            with you at the great day of account. --waterland.
      1913 webster

   syn: honest; unfeigned; unvarnished; real; true; unaffected;
        inartificial; frank; upright. see hearty.
        1913 webster
see also:
sincerer sincerest single discern hearty 

[2] : WordNet (r) 2.0

sincere
     adj 1: open and genuine; not deceitful; "he was a good man, decent
            and sincere"; "felt sincere regret that they were
            leaving"; "sincere friendship" ant: insincere
     2: characterized by a firm and humorless belief in the validity
        of your opinions; "both sides were deeply in earnest, even
        passionate"; "an entirely sincere and cruel tyrant"; "a
        film with a solemn social message" syn: earnest, in
        earnestp, solemn
see also:
insincere earnest in earnestp solemn 

[3] : Moby Thesaurus II by Grady Ward, 1.0

174 moby thesaurus words for "sincere":
   abandoned, aboveboard, actual, afire, ardent, artless, authentic,
   bluff, blunt, bona fide, born yesterday, bound,
   bound and determined, broad, brusque, burning, candid,
   card-carrying, childlike, committed, confiding, dear, decided,
   decisive, dedicated, definite, determined, devoted, devout, dinkum,
   direct, downright, earnest, explicit, faithful, fervent, fervid,
   fiery, flaming, following the letter, forthright, frank,
   frankhearted, free, free-speaking, free-spoken, free-tongued,
   genuine, good, guileless, heart-to-heart, heartfelt, hearty,
   heated, honest, honest-to-god, hot, hot-blooded, impassioned,
   in earnest, inartificial, ingenu, ingenuous, innocent, intense,
   intent, intent on, lawful, legitimate, lifelike, literal, loyal,
   meant, naive, natural, naturalistic, obstinate, on fire,
   on the level, open, openhearted, original, outspoken, passionate,
   perfervid, persevering, persistent, plain, plain-spoken, pure,
   purposeful, real, realistic, red-hot, relentless, resolute,
   resolved, rightful, round, serious, simon-pure, simple,
   simplehearted, simpleminded, single-hearted, single-minded,
   spirited, sterling, straight, straight-out, straightforward,
   sure-enough, tenacious, transparent, true, true to life,
   true to nature, true to reality, trustful, trusting, truthful,
   unadulterated, unaffected, unassumed, unassuming, unchecked,
   uncolored, unconcocted, unconstrained, uncopied, uncounterfeited,
   undesigning, undisguised, undisguising, undissembled,
   undissembling, undistorted, unequivocal, unexaggerated,
   unfabricated, unfanciful, unfeigned, unfeigning, unfictitious,
   unflattering, unguarded, unimagined, unimitated, uninvented,
   unpretended, unpretending, unpretentious, unqualified, unreserved,
   unrestrained, unromantic, unsimulated, unsophisticated, unspecious,
   unsuspicious, unsynthetic, unvarnished, unwary, vehement,
   veracious, verbal, verbatim, veridical, verisimilar, warm,
   white-hot, wholehearted, word-for-word, zealous

Sincere >> S Words
Sincere, definition of term: Sincere
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