boom

Boom is a term with several distinct meanings across different domains. In acoustics, a sonic boom is the sound associated with shock waves created when an object travels through air faster than the speed of sound. The effect is most pronounced when supersonic aircraft pass overhead, producing a sharp, thunder-like blast. The perceived intensity depends on altitude, atmospheric conditions, and flight path; sonic booms can cause minor structural vibrations and are subject to regulatory restrictions on overland flight.

In economics, a boom denotes a period of rapid expansion in economic activity, marked by rising gross domestic product, employment, income, and asset prices. Booms are part of the business cycle and are typically followed by a slowdown or recession, sometimes a bust.

In engineering, a boom is a long extension or arm used to reach or position equipment. Examples include a crane or excavator boom, a microphone or camera boom, and a sailing boom that carries the lower edge of a fore-and-aft sail.

In environmental and maritime contexts, a boom is a floating barrier designed to contain or control the spread of liquids such as oil spills or floating debris.

The term is also used in other phrases, such as "boom and bust" to describe cycles of rapid growth followed by contraction.