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chal·lenge (chălənj)
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n.
1.
a. A call to engage in a contest, fight, or competition: a challenge to a duel.
b. An act or statement of defiance; a call to confrontation: a challenge to the government's authority.
2. A demand for explanation or justification; a calling into question: a challenge to a theory.
3. A sentry's call to an unknown party for proper identification.
4. A test of one's abilities or resources in a demanding but stimulating undertaking: a career that offers a challenge.
5. A claim that a vote is invalid or that a voter is unqualified.
6. Law
a. A formal objection to the inclusion of a prospective juror in a jury.
b. A legal case testing the validity of an action taken, particularly by the government.
7. Immunology The induction or evaluation of an immune response in an organism by administration of a specific antigen to which it has been sensitized.
v. chal·lenged, chal·leng·ing, chal·leng·es
v.tr.
1.
a. To call to engage in a contest, fight, or competition: challenged me to a game of chess.
b. To invite with defiance; dare: challenged him to contradict her.
c. To confront or struggle with (something) as a test of one's abilities: rafters challenging the rapids.
2. To take exception to; call into question; dispute: a book that challenges established beliefs.
3. To order to halt and be identified, as by a sentry.
4. Law
a. To take formal objection to (a prospective juror).
b. To bring a legal case testing the validity of an action, particularly by the government.
5. To question the qualifications of (a voter) or the validity of (a vote).
6. To have due claim to; call for: events that challenge our attention.
7. To summon to action, effort, or use; stimulate: a problem that challenges the imagination.
8. Immunology To induce or evaluate an immune response in (an organism) by administering a specific antigen to which it has been sensitized.
v.intr.
1. To make or give voice to a challenge.
2. To begin barking upon picking up the scent. Used of hunting dogs.

[Middle English chalenge, from Old French, from Latin calumnia, trickery, false accusation; see CALUMNY. V., Middle English chalengen, from Old French chalangier, from Latin calumniārī, from calumnia.]

challenge·a·ble adj.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

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