English Dictionary

regular-duty

adj

(tennis) Describing a tennis ball having a thinner felt woven more tightly around the ball's core, designed for softer court surfaces such as clay.

He uses regular-duty batteries for his flashlight.

意味（1）

(tennis) Describing a tennis ball having a thinner felt woven more tightly around the ball's core, designed for softer court surfaces such as clay.

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. […] However, the regular-duty balls “play faster,” Collins said through a spokeswoman for the company.