The definition of a skeptic is someone inclined to doubt or question rather than just believe matters that are generally accepted.
(noun)A person who questions accepted beliefs is an example of a skeptic.
See skeptic in Webster's New World College Dictionary
adjective
Origin: L scepticus < Gr skeptikos, thoughtful, inquiring < skeptesthai, to consider: altered by metathesis < IE base *spe-, to peer > spy
noun
See skeptic in American Heritage Dictionary 4
also scep·tic
nounOrigin:
Origin: Latin Scepticus, disciple of Pyrrho of Elis
Origin: , from Greek Skeptikos
Origin: , from skeptesthai, to examine; see spek- in Indo-European roots
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