1A straight pitch in baseball (a fastball that doesn't break).
彼は試合で直球で三振を奪った。
He struck out the batter with a fastball in the game.
プロのピッチャーは直球の球威が重要だ。
For professional pitchers, the power of their fastball is important.
変化球よりも直球のコントロールを磨く練習をした。
I practiced improving control of my fastball rather than my breaking balls.
2A direct, blunt expression or approach (saying something straightforward without hedging).
彼女は直球で意見を言うので、話が早い。
She speaks frankly, so things move quickly.
面接で直球の質問をされて少し戸惑った。
I was a bit thrown by the blunt question in the interview.
上司に直球で給料の相談をした。
I asked my boss directly about my salary.