A method of locomotion used by some snakes, for traveling across loose surfaces such as sand.

Sidewinding is a type of locomotion unique to caenophidian snakes, used to move across loose or slippery substrates. It is most often used by the Saharan horned viper, Cerastes cerastes, and the sidewinder rattlesnake, Crotalus cerastes, to move across loose desert sands, but it is also used by Homalopsine snakes in Southeast Asia to move across tidal mud flats. Any number of caenophidian snakes can be induced to sidewind on artificial smooth surfaces, though difficulty in getting them to do so and their proficiency at it vary greatly.