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.
Insulin is a hormone that helps move sugar from the bloodstream into cells for energy. — Md Published, Verywell Health, 2 July 2026 Lower barometric pressure also means less force in the lungs to push oxygen from there into your bloodstream. — Bruce Y. Lee, Forbes.com, 5 July 2026 The lymphatic system collects that fluid from your tissues, filters it and returns it to your bloodstream. — Allison Palmer, Sacbee.com, 29 June 2026 The fluid that gets moved simply re-enters the bloodstream and gets processed by the liver and kidneys as usual, just faster than the body was managing alone. — Allison Palmer, Miami Herald, 30 June 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 7 Jul. 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

More from Merriam-Webster on bloodstream

Nglish: Translation of bloodstream for Spanish Speakers

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