Noun
a hard nonresilient rubber formed by vulcanizing natural rubber
Source: WordNetAlso in 1895 Berliner replaced the hard rubber used to make the discs with a shellac compound. citation Berliner's early records had poor sound quality, however. Source: Internet
A second component, a C-shaped hard rubber ring, is located between the crescent and the barrel. citation Ordinarily, the ring blocks the crescent from pushing down. Source: Internet
Nevins, 532–533 During another surgery, Cleveland was fitted with a hard rubber dental prosthesis that corrected his speech and restored his appearance. Source: Internet
Resistance to abrasion makes softer kinds of rubber valuable for the treads of vehicle tires and conveyor belts, and makes hard rubber valuable for pump housings and piping used in the handling of abrasive sludge. Source: Internet
Pemberton let his hand settle on the hard rubber ball topping the gear shift. Source: Internet
Highly trained and motivated U.S. Army crews could achieve 2 to 4 rounds per minute by using the hand-operated manual rammer, which was essentially a heavy steel pole with a hard rubber pad on one end. Source: Internet