incurve; incurve ball
Baseball term for a pitch that curves in toward the batter. The English loanword インカーブ is more common in modern Japanese.
His incurve is hard to hit.
I practiced throwing an incurve.
Compound of 内 (inside) + 曲 (curve) + 球 (ball), literally 'inside-curve ball'. A native Japanese coinage for the baseball pitch.