Definition of rubber
1 a
: one that rubs
b
: an instrument or object (such as a rubber eraser) used in rubbing, polishing, scraping, or cleaning
c
: something that prevents rubbing or chafing
2
[from its use in erasers]
a
: an elastic substance that is obtained by coagulating the milky juice of any of various tropical plants (as of the genera Hevea and Ficus), is essentially a polymer of isoprene, and is prepared as sheets and then dried — called also
caoutchouc, india rubber
b
: any of various synthetic rubberlike substances
c
: natural or synthetic rubber modified by chemical treatment to increase its useful properties (such as toughness and resistance to wear) and used especially in tires, electrical insulation, and waterproof materials
3
: something made of or resembling rubber: such as
a
: a rubber overshoe
b (1)
: a rubber tire
(2)
: the set of tires on a vehicle
c
: a rectangular slab of white rubber in the middle of a baseball infield on which a pitcher stands while pitching
d
: condom 1
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