hard rubber

American  

noun

1. rubber vulcanized with a large amount of sulfur, usually 25–35 percent, to render it stiff and comparatively inflexible.

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hard rubber British  

noun

1. a hard fairly inelastic material made by vulcanizing natural rubber See vulcanite

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Etymology

Origin of hard rubber

First recorded in 1855–60

Example Sentences

On June 27, United lost defender Brooks Lennon for six to eight weeks with a knee injury he sustained when he slipped on a hard rubber surface on the edge of Toronto’s playing field.

From Seattle Times • Jul. 6, 2022

"Either soft rubber or hard rubber, and/or plastic, and they're used when you don't need a real gun. In other words, it's not going to be firing blanks," he said.

From Fox News • Oct. 27, 2021

The only components that are not original are the hard rubber tires.

From Washington Times • Jan. 31, 2016

Others wander in on their own, drawn by the sound of jump ropes slapping the hard rubber floor or the staccato thwack, thwack, thwack of small hands pounding the heavy bags.

From Los Angeles Times • Apr. 28, 2015

Black, spit-shined police shoes with hard rubber soles cracked down on every inch of hardwood floor.

From "The Other Wes Moore: One Name, Two Fates" by Wes Moore