A demand for explanation or justification; a calling into question: a challenge to a theory.
A sentry's call to an unknown party for proper identification.
A test of one's abilities or resources in a demanding but stimulating undertaking: a career that offers a challenge.
A claim that a vote is invalid or that a voter is unqualified.
Law A formal objection to the inclusion of a prospective juror in a jury.
Immunology The induction or evaluation of an immune response in an organism by administration of a specific antigen to which it has been sensitized.
To call to engage in a contest, fight, or competition: challenged me to a game of chess.
To invite with defiance; dare: challenged him to contradict her. See Synonyms at defy.
To take exception to; call into question; dispute: a book that challenges established beliefs.
To order to halt and be identified, as by a sentry.
Law To take formal objection to (a prospective juror).
To question the qualifications of (a voter) or validity of (a vote).
To have due claim to; call for: events that challenge our attention.
To summon to action, effort, or use; stimulate: a problem that challenges the imagination.
Immunology To induce or evaluate an immune response in (an organism) by administering a specific antigen to which it has been sensitized.
To make or give voice to a challenge.
To begin barking upon picking up the scent. Used of hunting dogs.