proliferation

American  

[pruh-lif-uh-rey-shuhn] / prəˌlɪf əˈreɪ ʃən /

noun

1. the growth or production of cells by multiplication of parts.

2. a rapid and often excessive spread or increase.

   nuclear proliferation.

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proliferation British  

/ prəˌlɪfəˈreɪʃən /

noun

1. rapid growth or reproduction of new parts, cells, etc

2. rapid growth or increase in numbers

3. a great number

   done up in a proliferation of fancy frills

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Etymology

Origin of proliferation

First recorded in 1855–60; proliferate + -ion

Explanation

Proliferation is a rapid multiplication of parts or the increase in the number of something. Nuclear proliferation is a rapid increase of nuclear weapons. The proliferation of any living thing will often create an overpopulation problem and cause an environmental imbalance. A proliferation of fuzzy koala bears might seem kind of nice, but these cute little creatures would soon eat up all the eucalyptus, running out of food and causing problems for other species. We almost always use this word to describe stuff we don't want to increase rapidly. The excessive proliferation of mutated cells, for instance, is how cancer grows.

Example Sentences

The study found pro repair signals involving immune modulation, blood vessel and lymphatic development, fibroblast activation, myocardial salvage, smooth muscle cell proliferation, and neurogenesis in rat models.

From Science Daily • May 5, 2026

With the turnout expected to be about 30%, and the proliferation of candidates, the election is incredibly hard to predict.

From BBC • May 2, 2026

After a pandemic-era boom in demand that led to a proliferation of options, many e-bike companies have struggled with slowing interest and rising costs.

From Los Angeles Times • May 1, 2026

In recent months, the proliferation of agentic AI, or autonomous tools that can perform tasks on their own, has caused demand for computing power to far outstrip supply.

From The Wall Street Journal • Apr. 17, 2026

For following the proliferation of quotes had come something secret.

From "Typical American" by Gish Jen