Real Dictionary

rubber
uncountable noun: Rubber is a strong, waterproof, elastic substance made from the juice of a tropical tree or produced chemically. It is used for making tyres, boots, and other products.

rubber in American English 1
a person or thing that rubs, as in polishing, scraping, massaging, etc.
adjective: made of, containing, or coated with rubber
intransitive verb: to rubberneck
noun: a highly elastic solid substance, light cream or dark amber in color, polymerized by the drying and coagulation of the latex or milky juice of rubber trees and plants, esp Hevea and Ficus species

rubber in American English 2
a series of three games, two of which must be won to win the series
adjective: noting a deciding contest between two opponents who have previously won the same number of contests from each other
noun: a series or round played until one side reaches a specific score or wins a specific number of hands

rubber in Automotive Engineering
noun: Rubber is a strong, waterproof, elastic substance made from the juice of a tropical tree or produced chemically. It is used for making tires.

rubber in British English 1
noun: a cream to dark brown elastic material obtained by coagulating and drying the latex from certain plants, esp the tree Hevea brasiliensis

rubber in British English 2
noun: a match of three games