rubber

an elastic material obtained from the latex sap of trees (especially trees of the genera Hevea and Ficus) that can be vulcanized and finished into a variety of products

any of various synthetic elastic materials whose properties resemble natural rubber

an eraser made of rubber (or of a synthetic material with properties similar to rubber); commonly mounted at one end of a pencil

contraceptive device consisting of a sheath of thin rubber or latex that is worn over the penis during intercourse

a waterproof overshoe that protects shoes from water or snow

coat or impregnate with rubber; "rubberize fabric for rain coats"

returned for lack of funds; "a rubber check"; "a no-good check"