Dry cleaning is any cleaning process for clothing and textiles using a solvent other than water. Dry cleaning still involves liquid, but clothes are instead soaked in a water-free liquid solvent (usually non-polar, as opposed to water which is a polar solvent). Tetrachloroethylene (perchloroethylene), known in the industry as "perc", is the most widely used solvent. Alternative solvents are 1-bromopropane and petroleum spirits.
Most natural fibers can be washed in water but some synthetics (e.g., viscose, lyocell, modal, and cupro) react poorly with water and should be dry-cleaned if possible. The expression "dry cleaner" is used both for the shop providing dry cleaning service and for the operator of the machine that performs the process.