skeptical

adj. doubtful, questioning the validity of claims

"Skeptic" redirects here. For magazines, see Skeptic (magazine) and The Skeptic In ordinary usage, skepticism or scepticism (Greek: skeptomai, to look about, to consider; see also spelling differences) refers to an attitude of doubt or a disposition to incredulity either in general or toward a particular object, the doctrine that true knowledge or knowledge in a particular area is uncertain, or the method of suspended judgment, systematic doubt, or criticism that is characteristic of skeptics (Merriam–Webster).
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(a.)
Of or pertaining to a sceptic or skepticism; characterized by skepticism; hesitating to admit the certainly of doctrines or principles; doubting of everything.
  

(a.)
Doubting or denying the truth of revelation, or the sacred Scriptures.
  

Adjective
1. denying or questioning the tenets of especially a religion; "a skeptical approach to the nature of miracles"
(synonym) disbelieving, sceptical, unbelieving
(similar) incredulous
2. marked by or given to doubt; "a skeptical attitude"; "a skeptical listener"
(synonym) doubting, questioning, sceptical
(similar) distrustful