sodium hydroxidesodium hydroxide
a white, deliquescent substance, NaOH, in the form of a powder, flakes, sticks, etc.: it is a strong caustic base, widely used in chemistry, oil refining, etc.
A white deliquescent solid, NaOH, that is a strong base used in the manufacture of chemicals and soaps and in petroleum refining. Also called caustic soda . Also called lye .