bathtub curve

noun

mathematics

: a curve with large initial and final values and a low, flat region in the middle

The trend of this cracking over an airplane's life follows what is known as the "bathtub" curve, so-called because its shape resembles that of a bathtub. The line of the curve charts the rise and fall in the number of cracks a typical fleet of aircraft experiences over its lifetime.

—Oswald Johnston, Los Angeles Times, 1 May 1988

Note: The bathtub curve is often used to describe the rate of failure of a product such as an electronic device or a piece of furniture. Such products often have a high failure rate in the beginning of their lifespan (as because of manufacturing defects) and at the end of their lifespan (as they wear out and break down).

Word History

First Known Use

1964, in the meaning defined above

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