challenge

fe’l verb

1. To invite (someone) to take part in a competition. We challenged the boys next door to a game of football.
2. To dispute (something). to challenge the accuracy of a statement or of a quotation
3. To question or demand the countersign from (one who attempts to pass the lines). The sentinel challenged us with "Who goes there?"
4. To dare (someone).

ot noun

1. A confrontation; a dare.
2. A difficult task, especially one that the person making the attempt finds more enjoyable because of that difficulty.
3. A procedure or action.
4. The opening and crying of hounds at first finding the scent of their game.