A Multiplier (arithmetic) A number by which another (the multiplicand) is to be multiplied. (multiplier) × (multiplicand) = (product) (grammar) An adjective indicating the number of times something is to be multiplied. (economics) A ratio used to estimate total economic effect for a variety of economic activities. (physics) Any of several devices used to enhance a signal (physics, obsolete) a coil; when Johann Schweigger in 1820 invented the electric coil, increasing the electro-magnetic field from a single wire, this invention was called a multiplier. A multiplier onion.