catheter

American  

[kath-i-ter] / ˈkæθ ɪ tər /

noun

Medicine/Medical.

1. a flexible or rigid hollow tube employed to drain fluids from body cavities or to distend body passages, especially one for passing into the bladder through the urethra to draw off urine or into the heart through a leg vein or arm vein for diagnostic examination.

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catheter British  

/ ˈkæθɪtə /

noun

1. med a long slender flexible tube for inserting into a natural bodily cavity or passage for introducing or withdrawing fluid, such as urine or blood

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catheter Scientific  

/ kăth′ĭ-tər /

1. A hollow, flexible tube inserted into a body cavity, duct, or vessel to allow the passage of fluids or distend a passageway.

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catheter Cultural  

1. A thin tube inserted into one of the channels or blood vessels in the body to remove fluids, create an opening into an internal cavity, or administer injections.

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Etymology

Origin of catheter

1595–1605; < Late Latin < Greek kathetḗr kind of tube, literally, something sent or let down, equivalent to kathe- (variant stem of kathiénai, equivalent to kat- cata- + hiénai to send, let go) + -tḗr agent suffix

Compare meaning

How does catheter compare to similar and commonly confused words? Explore the most common comparisons:

• cannula vs. catheter

Explanation

A catheter is a thin, flexible tube that's inserted into the body to draw liquids out or keep a pathway open. It’s the kind of thing you’d get in the hospital. The word catheter is from the Greek kathienai which means, "thrust in or let down." That’s what happens when that small tube goes into your body and lets fluid out. If you have surgery in the belly area, you’ll probably need a catheter to drain the urine until you can go to the bathroom by yourself again. A catheter can also be inserted into other organs, like through a blood vessel and into the heart, to see what's going on.

Example Sentences

The experimental therapy is administered through a catheter inserted into tiny holes in the skull.

From MarketWatch • Mar. 9, 2026

Her Hickman line, a catheter used to administer drugs, later became infected.

From BBC • Jan. 17, 2026

Farapulse is a catheter ablation technology using PFA, or pulsed field ablation.

From Barron's • Jan. 16, 2026

An epidural is an invasive procedure in which an anesthetic is delivered into the body via a catheter inserted into the lower back.

From The Wall Street Journal • Oct. 12, 2025

Since my last visit, a nurse had inserted a catheter into his penis, which drew the urine out through a tube and into a bag that sat at the foot of his chair.

From "Tuesdays with Morrie" by Mitch Albom