In the forefront of new developments. The analogy is to the sharp edge of a knife or other tool, which is in front during the act of cutting. The term came into use in the field of scientific and technologic research about 1950 and soon was extended to practically any area of endeavor. For example, in a radio interview on November 14, 1989, Craig Wich, the director of Opera Lab, explained that his organization’s approach to integrating movement, emotion, and singing was at the cutting edge of a new approach to opera (Boston, WCRB). A similar metaphor widely used is the leading edge. Dating from the 1870s and at first describing only the forward edge of a rudder or propeller blade that cuts the water, it was later expanded to mean any device or system that extends an aircraft’s speed, altitude, and range, and eventually transferred to the vanguard of anything—“the leading edge of technology,” for example.