also: ロジンバッグ
noun
rosin bag
A small cloth bag filled with rosin powder, used by athletes such as baseball pitchers, gymnasts, and weightlifters to improve grip.
ピッチャーはマウンドでロージンバッグを手に取った。
The pitcher picked up the rosin bag on the mound.
体操選手は滑り止めにロージンバッグを使う。
Gymnasts use a rosin bag to prevent slipping.