bloodstream

noun

blood·​stream ˈbləd-ˌstrēm How to pronounce bloodstream (audio)
1
: the flowing blood in a circulatory system
2
: a mainstream of power or vitality
… introduce into the economic bloodstream a large amount of money …—Harper's

Examples of bloodstream in a Sentence

The drug is now entering the bloodstream.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Zinc helps your pancreas produce and release insulin, the hormone that moves blood sugar from your bloodstream into your cells. — Brittany Lubeck, Verywell Health, 28 Oct. 2026 The first is Candida auris, a fungus that can cause anything from mild skin infections to severe, and potentially life-threatening, bloodstream infections. — ABC News, 27 Oct. 2026 Unlike existing treatments that primarily neutralize IgE circulating in the bloodstream, the company aims to detach IgE from immune cells. — Neetika Walter, Interesting Engineering, 27 Oct. 2026 Normally, insulin helps move glucose from the bloodstream into muscle cells, where it can be stored as glycogen for later use. — Angelica Stabile, FOXNews.com, 27 Oct. 2026 See All Example Sentences for bloodstream

Word History

First Known Use

13th century, in the meaning defined at sense 1

Time Traveler
The first known use of bloodstream was in the 13th century

Rhymes for bloodstream

See All Rhymes for bloodstream

Browse Nearby Words

bloodstone
bloodstream
bloodsucker
See all Nearby Words

Cite this Entry

“Bloodstream.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/bloodstream. Accessed 1 Nov. 2026.

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Kids Definition

bloodstream

noun
blood·​stream -ˌstrēm How to pronounce bloodstream (audio)
: the flowing blood in a living thing with a circulatory system

Medical Definition

bloodstream

noun
blood·​stream -ˌstrēm How to pronounce bloodstream (audio)
: the flowing blood in a circulatory system
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