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

The use of sting-ball grenades was inherently indiscriminate, the suit says, because the weapons exploded with hard rubber shrapnel firing in every direction.

From Washington Post

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

"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

Salmomée Souag, 23, of Portland, Ore., shared a picture showing a hard rubber pellet she found in the street that appeared to be a riot-control device known as a baton round.

From Washington Post

Enter through the back parking lot and you find yourself in a large, darkened room with hard rubber flooring and thick curtains pulled over a floor-to-ceiling mirror at the front of the room.

From Los Angeles Times