Sincere1. (superl.) Pure; unmixed; unadulterated.
2. (superl.) Whole; perfect; unhurt; uninjured.
3. (superl.) 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.
4. (superl.) Honest; free from hypocrisy or dissimulation; as, a sincere friend; a sincere person.
Thesaurus Entries
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