life cycle

American  

noun

1. Biology. the continuous sequence of changes undergone by an organism from one primary form, as a gamete, to the development of the same form again.

2. a series of stages, as childhood and middle age, that characterize the course of existence of an individual, group, or culture.

3. any similar series of stages.

   the life cycle of a manufactured product.

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life cycle British  

noun

1. the series of changes occurring in an animal or plant between one development stage and the identical stage in the next generation

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life cycle Scientific  

1. The series of changes in the growth and development of an organism from its beginning as an independent life form to its mature state in which offspring are produced. In simple organisms, such as bacteria, the life cycle begins when an organism is produced by fission and ends when that organism in turn divides into two new ones. In organisms that reproduce sexually, the life cycle may be thought of as beginning with the fusion of reproductive cells to form a new organism. The cycle ends when that organism produces its own reproductive cells, which then begin the cycle again by undergoing fusion with other reproductive cells. The life cycles of plants, algae, and many protists often involve an alternation between a generation of organisms that reproduces sexually and another that reproduces asexually.

2. See more at alternation of generations

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Etymology

Origin of life cycle

First recorded in 1870–75

Example Sentences

Its life cycle includes a journey of 11,000 kilometers from Andean headwaters to coastal nursery areas.

From Science Daily • Mar. 26, 2026

And an indicator’s life cycle is shortened to the extent it becomes widely known.

From MarketWatch • Mar. 23, 2026

But it’s worth remembering a theory developed by economist Carlota Perez in the early 2000s: Big Bang technologies follow a predictable three-step life cycle of installation boom, mid point financial crisis and longer term adoption.

From Barron's • Mar. 19, 2026

The pattern illustrated his grand conception of the sequoia life cycle.

From Los Angeles Times • Mar. 13, 2026

The fate of a star, the end of its life cycle, depends very much on its initial mass.

From "Cosmos" by Carl Sagan

Related Words

• biological clock