What does 王者 mean?
王者 is a Japanese noun meaning “king; monarch; ruler” in English. It can also be translated as “champion” depending on context. It is written as 王者 in kanji, おうじゃ in hiragana, and ouja in romaji. This word is part of JLPT N1 vocabulary.
Example sentence
カリフォルニアには有名な大木、つまり、いわゆる森の王者がある。
In California are the famous big trees, or "forest kings" as they are called.