by-product

American  

[bahy-prod-uhkt] / ˈbaɪˌprɒd əkt /

noun

1. a secondary or incidental product, as in a process of manufacture.

2. the result of another action, often unforeseen or unintended.

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by-product British  

noun

1. a secondary or incidental product of a manufacturing process

2. a side effect

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by-product Scientific  

/ bī′prŏd′əkt /

1. Something produced in the process of making something else. When plants produce carbohydrates by photosynthesis, oxygen is released as a by-product. Asphalt and paraffin are by-products of the process of refining crude oil into gasoline.

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Etymology

Origin of by-product

First recorded in 1900–05

Example Sentences

Existing by-product is already stored in a permanent disposal facility "constructed and managed to ensure the material does not impact on the surrounding environment," the company said.

From Barron's • Apr. 22, 2026

Through it all, however, West struggled with depression and a sense of self-loathing, and had trouble with intimacy, much of it a by-product of a hardscrabble childhood in West Virginia with a domineering father.

From Los Angeles Times • Apr. 14, 2026

He adds that using this by-product increases the nutritional value of bread while lowering the environmental footprint of sunflower oil production.

From Science Daily • Feb. 8, 2026

Dermot O'Brien from the company said the dust was a by-product of its manufacturing process to make kitchen doors.

From BBC • Feb. 1, 2026

“Let’s take a look, shall we? Poultry by-product meal, soy protein isolate, corn gluten meal, soy flour...”

From "Sir Fig Newton and the Science of Persistence" by Sonja Thomas

Related Words

• outgrowth