English Dictionary

extra-duty

形容詞

比較不可

(tennis) Describing a tennis ball having a thicker felt woven more loosely around the ball's core, designed for hard court surfaces such as asphalt or concrete.

日本語の意味

（テニス用語）硬いコート（アスファルトやコンクリートなど）向けに設計され、ボールのコアの周りにゆるく編まれた厚めのフェルトが用いられているテニスボールを指す。

I always buy extra-duty tennis balls for our weekend matches on the community's concrete courts.

私は週末の試合のために、ハードコート（アスファルトやコンクリート）用でフェルトが厚くゆるく織られているテニスボールをいつも買います。

意味（1）

(tennis) Describing a tennis ball having a thicker felt woven more loosely around the ball's core, designed for hard court surfaces such as asphalt or concrete.

The men at the U.S. Open use what is known as an “extra-duty” ball, which means the felt on the outside of the ball is woven slightly more loosely than the “regular-duty” ball the women use. […] Extra-duty balls are the balls of choice for outdoor hardcourts, like those at the U.S. Open, except when they are not.