Definition of crank up

The origin of the phrase "crank up" can be traced back to the mid-19th century when steam engines were widely used in various industries such as transportation and manufacturing. The crankshaft, a vital mechanical component of a steam engine, converted the back-and-forth motion of the pistons into rotational force that was then employed to drive wheels and other machinery. To operate a steam engine, the engineer would crank the crankshaft manually to start the pistons moving, essentially turning a handle several times to build enough momentum for the engine to self-sustain. This action was termed "cranking up" the engine, and eventually, it came to signify the broader notion of increasing the speed or intensity of anything, be it an audio system, a motorist's engine, or an activity's pace. The phrase has since gained widespread usage in various contexts due to its straightforward and vivid definition, alluding to the physical act of spinning or twisting a crank to get things going. In essence, the term "crank up" encompasses the concept of breaking through initial resistance and pumping up the power, highlighting the persuasive and energetic overtones of this common expression.