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

One wonders about the butterfly effect caused by the swish of Jadeja's blade.

From BBC • Jul. 22, 2025

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

From Salon • May 29, 2025

Although we may commonly use the phrase to denote the seeming interconnectedness of our own lives, the term "butterfly effect" is sometimes associated with chaos theory.

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