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confident; assured; self-assured; firm; strong; cocksure
bullish
彼は交渉で常に強気の姿勢を見せた。
He always showed a confident attitude in negotiations.
株価が上がり投資家は強気になった。
Stock prices rose and investors became bullish.
彼女は強気な発言で相手を圧倒した。
She overwhelmed the opponent with bold statements.