(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.

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

plural of Challenger

Difficult, hard to do.

present participle of challenge

The act of making a challenge.

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.