IPA: /ˌkɒntrəˈdɪktə/
KK: /kɒntrəˈdɪktər/
A person who says the opposite of what someone else has said, often to challenge or dispute their statement.
During the debate, she played the role of a contradicter, questioning every point made by her opponent.
Contradictor → It is formed from "contra-" (meaning against) and "dicere" (meaning to speak). The word refers to someone who speaks against or opposes a statement or argument.
Think of someone who 'speaks against' ('contra-' means against and 'dicere' means to speak') — that's what a contradictor does.