challenger

/ˈtʃæləndʒər/
noun
  1. A person who competes against someone else, especially for a title or position.
    • The young challenger defeated the reigning champion in the final match.
    • In the election, the challenger argued for new policies.
    • She is a strong challenger for the position of team captain.
  2. A person who questions or disputes something, such as an idea or authority.
    • He became a challenger to the company's safety practices.
    • The scientist was a challenger of the old theory, proposing a new model.
    • As a challenger of unfair rules, she spoke up at the meeting.
What does "challenger" mean? | whatsthatwordmean | whatsthatwordmean