: to say or show that (something) may not be true, correct, or legal
: to question the action or authority of (someone)
law : to question whether (someone) should serve on a jury
: a difficult task or problem : something that is hard to do
: an action, statement, etc., that is against something : a refusal to accept something as true, correct, or legal
: an invitation to compete in a game, fight, etc.
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