The solid mineral material forming part of the surface of the earth and other similar planets, exposed on the surface or underlying the soil or oceans. A large piece of rock that has become detached from a cliff or mountain; a boulder. Used in similes and metaphors to refer to someone or something that is extremely strong, reliable, or hard. Money. Rock music. A gentle movement to and fro or from side to side. Move gently to and fro or from side to side. Dance to or play rock music. Wear (a garment) or affect (an attitude or style), especially in a confident or flamboyant way.