Meaning of extra-duty | Babel Free

Definitions

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.

not-comparable

Examples

“Coordinate term: regular-duty”

“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.”

CEFR level