noun

ICU

eye-see-YOO

ICU (noun) means the part of a hospital that treats patients who are critically ill and need constant monitoring and life-support equipment. Example: “He spent nine days in the ICU after the crash.”

noun

The part of a hospital that treats patients who are critically ill and need constant monitoring and life-support equipment.

"He spent nine days in the ICU after the crash."

"Every ICU bed in the region was occupied that winter."

abbreviation

informal, texting Used in messages and online as a short way of writing I see you, either literally or to show that you have noticed and approve of what someone is doing.

"icu already up at 6am, respect."

"ICU in the background of that photo."

How to Use ICU

Learner’s notes

In plain EnglishThe hospital ward for the most seriously ill patients.

When to use it

The medical sense is neutral and standard; the texting sense is very informal and usually lower case.

Memory tip

NICU is the neonatal intensive care unit, for newborn babies, and is often said NICK-yoo.

Trace the full origin ↓

Easily confused with

ITU HDU NICU A&E →

Common pairings

admitted to the ICU ICU bed neonatal ICU ICU nurse

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Fill the Gap

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He spent nine days in the _____ after the crash.

Etymology

An initialism of intensive care unit.

Origin: English

Synonyms

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intensive care unit critical care unit ITU

Frequently Asked Questions

What is the difference between ICU and HDU?

An intensive care unit treats the sickest patients, often with mechanical ventilation and one nurse per patient. A high dependency unit is a step down: closer monitoring than a normal ward, but less support and a lower staffing ratio.

What does ICU mean in texting?

It usually stands for I see you. Depending on tone it can mean literally spotting someone, or acknowledging something impressive they have done.

Is ICU the same as ITU?

In practice yes. Intensive therapy unit is an older British term for the same kind of ward, and many UK hospitals use ICU, ITU and critical care interchangeably.

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Vocabulary lists that include ICU:

Words That End With U