One who challenges; especially, one who plays against the current champion of a game or contest in hopes of winning and becoming the new champion.

plural of challenger

(rail transport) a steam locomotive of the 4-6-6-4 wheel arrangement.

A space shuttle, named after HMS Challenger (1858), destroyed on January 28, 1986 with loss of its seven-member crew.

plural of Challenger

Able to be challenged or disputed.

An antagonization or instigation intended to convince a person to perform an action they otherwise would not. / A bid to overcome something. / (sports) An attempt to take possession; a tackle.

(transitive) To invite (someone) to take part in a competition. / (transitive) To dare (someone). / (transitive) To dispute (something). / To call something into question or dispute.

simple past tense and past participle of challenge

(euphemistic) Lacking some physical or mental attribute or skill ; used after adverbs to make politically correct adjectives.