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 moneyHarper'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.
Both are preventative monoclonal antibodies, which deliver antibodies directly into the bloodstream to provide immediate protection. Annika Kim Constantino, CNBC, 26 June 2025 Beta-glucan slows the absorption of sugar into the bloodstream, preventing post-meal blood sugar spikes.25 Maintaining optimal blood sugar levels is essential for keeping yourself energized, preventing chronic disease, managing your mood and hunger, and more. Jillian Kubala, Health, 25 June 2025 The key difference is that these drugs, due to clever chemical engineering, last in the bloodstream for a solid week, rather than just a single day. Paul Sisson, San Diego Union-Tribune, 23 June 2025 Typically, these inflammatory molecules are transmitted via the bloodstream to whichever site they’re needed; in healthy individuals, the blood-brain barrier (BBB) usually prevents them from entering the brain. Mark Travers, Forbes.com, 21 June 2025 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

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Cite this Entry

“Bloodstream.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/bloodstream. Accessed 6 Jul. 2025.

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

Last Updated: - Updated example sentences
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