hard rubber

noun

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

hard rubber

noun

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

Word History and Origins

Origin of hard rubber¹

First recorded in 1855–60

Example Sentences

We put an extra foot of height in the basement ceiling, we’ll put a bathroom down there, and you create a true home gym with a hard rubber floor and a mirrored wall and a ballet bar for bar classes.

From Time

Cutting boards come in three major categories: wood (including bamboo), plastic, and hard rubber.

From The Daily Beast

In a fork of this arm hangs a round, black, trumpet-shaped, hard rubber tube.

From Project Gutenberg

They are made in wood and in hard rubber, the latter being most durable; their uses are so obvious as to require no explanation.

From Project Gutenberg

Drawing squares or T squares, as they are termed, are made of wood, of hard rubber and of steel.

From Project Gutenberg

This consists, in its essentials, of a hard rubber disc provided with a copper or brass segment.

From Project Gutenberg

The hard rubber being a non-conductor of electricity, prevents the flow of the current at all other times.

From Project Gutenberg