Noun

(en noun)

A confrontation; a dare.

# An instigation or antagonization intended to convince a person to perform an action they otherwise would not.

#*{{quote-magazine, date=2013-11-30, volume=409, issue=8864, magazine=(The Economist), author=Paul Davis

, title= Letters: Say it as simply as possible , passage=Congratulations on managing to use the phrase “preponderant criterion” in a chart (“ On your marks”, November 9th). Was this the work of a kakorrhaphiophobic journalist set a challenge by his colleagues, or simply an example of glossolalia?}}

# A bid to overcome something.

#* {{quote-news, year=2012, date=May 5, author=Phil McNulty, work=BBC Sport

, title= Chelsea 2-1 Liverpool , passage=For Liverpool, their season will now be regarded as a relative disappointment after failure to add the FA Cup to the Carling Cup and not mounting a challenge to reach the Champions League places.}}

# (sports) An attempt to take possession; a tackle

#* {{quote-news, year=2011, date=October 1, author=Saj Chowdhury, work=BBC Sport

, title= Wolverhampton 1-2 Newcastle , passage=Argentine midfielder Jonas Gutierrez added a superb second when he surged past four challenges to fire in low.}}

# A summons to fight a duel; also, the letter or message conveying the summons.

# The act of a sentry in halting a person and demanding the countersign, or (by extension) the action of a computer system demanding a password, etc.

A difficult task, especially one that the person making the attempt finds more enjoyable because of that difficulty.

(label) A procedure or action.

# (legal, rare) A judge's interest in the result of the case for which he or she should not be allowed to sit the case, e.g. a conflict of interest.

# The act of appealing a ruling or decision of a court of administrative agency.

# The act of seeking to remove a judge, arbitrator or other judicial or semi-judicial figure for reasons of alleged bias or incapacity.

# (label) An exception to a person as not legally qualified to vote. The challenge must be made when the ballot is offered.

(label) The opening and crying of hounds at first finding the scent of their game.

Noun

(en noun)

The act of achieving or performing; a successful performance; accomplishment

* {{quote-book, year=1963, author=(Margery Allingham)

, title=(The China Governess) , chapter=1 citation , passage=The original family who had begun to build a palace to rival Nonesuch had died out before they had put up little more than the gateway, so that the actual structure which had come down to posterity retained the secret magic of a promise rather than the overpowering splendour of a great architectural achievement .}}

* {{quote-magazine, year=2012, month=March-April

, author= , title=Well-connected Brains , volume=100, issue=2, page=171 , magazine=(American Scientist) citation , passage=Creating a complete map of the human connectome would therefore be a monumental milestone but not the end of the journey to understanding how our brains work. The achievement will transform neuroscience and serve as the starting point for asking questions we could not otherwise have answered, […].}}

A great or heroic deed or feat; something accomplished by valor or boldness

* [The exploits] of the ancient saints do far surpass the most famous achievements of pagan heroes. - (Isaac Barrow)

* The highest achievements of the human intellect. - (Thomas Babington Macaulay)

(heraldry) An escutcheon or ensign armorial; now generally applied to the funeral shield commonly called hatchment.

(video games) An award for completing a particular task or meeting an objective in a video game.