butterfly effect

American  

noun

1. a cumulatively large effect that a very small natural force may produce over a period of time.

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butterfly effect British  

noun

1. the idea, used in chaos theory, that a very small difference in the initial state of a physical system can make a significant difference to the state at some later time

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butterfly effect Scientific  

/ bŭt′ər-flī′ /

1. A phenomenon in which a small perturbation in the initial condition of a system results in large changes in later conditions. Such phenomena are common in complex dynamical systems and are studied in chaos theory.

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Usage

What does butterfly effect mean? The butterfly effect is the idea that small events can have a large, unpredictable influence on the future. How is butterfly effect pronounced?[ buht-er-flahy ih-fekt ] What are some other words related to butterfly effect?

• chaos theory
• fractals
• domino effect
• snowball
• divergence

Etymology

Origin of butterfly effect

First recorded in 1980–85; so called from the notion that the fluttering of a butterfly's wings may set off currents that will grow into a large storm

Example Sentences

Mr Surcouf said the biggest concern for local charities was the potential "butterfly effect" of US policies being mirrored elsewhere.

From BBC • Aug. 4, 2025

“The butterfly effect was not me, it was Comey—it was what Comey did with that,” Weiner said.

From Salon • May 29, 2025

Goldenfeld said their work represents a more extreme version of the butterfly effect, first described by mathematician and meteorologist Edward Lorenz in 1969.

From Science Daily • Mar. 12, 2024

The next leg of our butterfly effect journey happens in a form of knowledge sharing.

From National Geographic • Oct. 2, 2023

I am hyperaware—as he leaves me, as I am surrounded by other people—of the perilous nature of what I am attempting, of the butterfly effect that threatens to flutter its wings with every interaction.

From "Every Day" by David Levithan