Precipitation is a term used in meteorology to describe any product of the condensation of atmospheric water vapor that falls from clouds due to gravitational pull. It can come in many forms, including drizzle, rain, sleet, snow, ice pellets, graupel, and hail. Precipitation is one of the three main steps of the water cycle, along with evaporation and condensation.

In addition to its meteorological definition, precipitation can also refer to a chemical reaction in which a solid substance forms and separates from a liquid solution. This solid substance is called a precipitate, and its formation suggests the presence of a chemical reaction. For example, when a silver nitrate solution is poured into a sodium chloride solution, a chemical reaction occurs, producing a white silver chloride precipitate. Another example is the formation of a yellow lead(II) iodide precipitate when a potassium iodide solution reacts with a lead(II) nitrate solution.

Salt is not a precipitate, as it is a compound that is soluble in water and does not form a solid substance when dissolved.