taper

Taper is a term with multiple meanings across disciplines. At its core, a taper is something that becomes gradually thinner or narrower from one end to the other. As a verb, to taper also means to reduce gradually in size, amount, intensity, or frequency.

In physical design and engineering, a taper describes a portion of a component whose diameter decreases along its length. Tapered shapes appear in candles, shafts, pins, dowels, and fittings. A taper can enable a snug connection or a gradual fit, such as a tapered pin or a pipe thread that helps form a seal as it is tightened. The rate of change is often described by a taper ratio or an angle.

In manufacturing and assembly, tapered joints and fittings are used to align parts, facilitate assembly, or transmit loads through a changing cross-section.

In exercise science, tapering refers to a planned reduction in training load before a competition to preserve performance while allowing recovery.

In macroeconomics, tapering denotes the gradual reduction of the pace of central bank asset purchases, a policy step used to wind down quantitative easing without an abrupt shift in stance.