foam rubber(n = noun.substance) - spongy rubber; made by introducing air bubbles before vulcanization and used for cushioning or upholstery;
is a kind of foam, caoutchouc, gum elastic, india rubber, natural rubber, rubber

assam rubber, buna rubber, butyl rubber, cold rubber, crepe rubber, foam, foam at the mouth, hard rubber, india rubber, mistletoe rubber plant, natural rubber, par'a0 rubber, para rubber, para rubber tree, polyurethane foam, rubber, rubber band, rubber boa, rubber boot, rubber bullet, rubber cement, rubber eraser, rubber plant, rubber stamp, rubber tire, rufous rubber cup, sea foam, shaving foam, silicone rubber, synthetic rubber