Definition of the word amplitude

The word "amplitude" comes from Latin, specifically from "amplitudo," which means "breadth" or "width." This Latin term is derived from "amplus," meaning "wide" or "large," and the suffix "-tudo," which forms an abstract noun indicating a quality or state. In the 15th century, "amplitude" referred to the extent or breadth of something, such as a distance or a range. In the 17th century, mathematicians and physicists applied the term to describe the magnitude or size of a quantity, such as the amplitude of a wave or the amplitude of sound wave. In modern physics and engineering, "amplitude" is used to describe the maximum amount by which a quantity oscillates or varies above and below its equilibrium value. This sense of the word has its roots in the original Latin meaning of "broadness" or "width," as it describes the value that spans the limits of an oscillation or variation.