TRUTHFUL

adj. speaking the truth, honest; true; accurate, faithful to reality

The meaning of the word truth extends from honesty, good faith, and sincerity in general, to agreement with fact or reality in particular. The term has no single definition about which the majority of professional philosophers and scholars agree. Various theories of truth continue to be debated. There are differing claims on such questions as what constitutes truth; how to define and identify truth; the roles that revealed and acquired knowledge play; and whether truth is subjective, relative, objective, or absolute. This article introduces the various perspectives and claims, both today and throughout history.
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Adjective
1. expressing or given to expressing the truth; "a true statement"; "gave truthful testimony"; "a truthful person"
(synonym) true
(antonym) untruthful
(similar) honest
2. conforming to truth; "I wouldn't have told you this if it weren't so"; "a truthful statement"
(synonym) so(p)
(similar) true

(a.)
Full of truth; veracious; reliable.
  

Synonyms and related words:
accurate, actual, ascertained, attested, authenticated, candid, categorically true, certain, certified, confirmed, corroborated, demonstrated, determined, documentary, earnest, effectual, established, factual, faithful, forthright, frank, historical, honest, not in error, objectively true, proved, real, realistic, reliable, sincere, straightforward, substantiated, sure-enough, TRUE, true as gospel, true to life, true-meaning, true-speaking, true-tongued, trustworthy, truth-bearing, truth-declaring, truth-desiring, truth-filled, truth-guarding, truth-loving, truth-passing, truth-speaking, truth-telling, unconfuted, undenied, undoubted, unembellished, unerroneous, unfallacious, unfalse, unmistaken, unquestionable, unrefuted, unvarnished, validated, veracious, veridical, verified, veritable