Medical terms explained: hospital words in plain language for patients and families

Hospital staff speak a second language all day, and it is easy to forget that nobody else does. Families nod along to words like NPO, PRN and stable, then look them up in the parking lot. For a patient who cannot easily speak, it is harder still: they cannot interrupt to ask what a word means, so they lie there wondering.

Below are common words, explained in general terms. What any of them means for one particular patient is a question for the care team, and it is always fine to ask.

Tests and scans

• CT scan: a series of X-ray pictures taken from many angles and put together into cross-sections of the body. It is usually quick.
• MRI: detailed pictures made with a strong magnet and radio waves instead of X-rays. It is loud, takes longer, and staff will ask about metal in the body first.
• Labs or bloodwork: tests on a blood sample, often drawn early in the morning.
• Swallow study or swallow evaluation: a check, often by a speech-language pathologist, of whether food and drink go down safely.
• Vitals: the basic measurements (temperature, heart rate, breathing rate and blood pressure), often with an oxygen reading.
• Pulse oximeter: the clip on a finger that estimates how much oxygen is in the blood.

Lines, tubes and fluids

• IV: a thin tube placed in a vein to give fluids or medicine.
• Saline: sterile salt water. It is used to give fluids, to flush an IV line and to carry some medicines.
• Catheter: a thin tube. A urinary catheter drains the bladder; other catheters go into blood vessels.
• Ventilator: the machine that breathes for a patient through a breathing tube. Intubated means the tube is in place.
• Feeding tube: a tube that delivers nutrition directly to the stomach, through the nose or through the belly.

Orders and shorthand

• NPO: nothing by mouth, often before a procedure or until a swallow check is done. It usually includes water.
• PRN: as needed. A PRN pain medicine is given when the patient asks or needs it, not on a fixed schedule.
• Stable: the condition is not changing quickly right now. It does not always mean good; ask what it means today.
• Discharge planning: the work of getting ready to leave the hospital, usually led by a case manager or social worker.
• PT, OT and SLP: physical therapy (moving and walking), occupational therapy (daily tasks like dressing) and speech-language pathology (speech, language and swallowing).

People you will meet

• Hospitalist: a doctor whose job is caring for patients in the hospital. It is often not the person's own primary doctor.
• Attending and residents: in a teaching hospital, the attending is the senior doctor responsible for care; residents are doctors in training working with them.
• Charge nurse: the nurse running the unit on a shift, a good person to ask when something is not working.
• Case manager or social worker: the people who plan discharge, equipment and services at home.
• Rapid response team: a team the staff call to the bedside quickly when a patient's condition changes. Families can often ask for one too; ask the nurse how it works on the unit.

Make the explanations land

Three habits help. First, ask the question behind the word: what does that mean for today, and what happens next? Second, repeat it back in your own words (so the swallow study decides whether the tube can come out?) and let the clinician correct you. Third, write it down, or ask them to. A shared notebook by the bed, or notes in an app, saves the family from relaying half-remembered explanations to each other.

Include the patient. Explanations are often directed at whoever is standing, but the person in the bed usually understands far more than they can say. Face them when you ask, and give them a way to ask their own questions.

Medical Words in ExpressAgain

ExpressAgain's Medical Words is a plain-language dictionary built for exactly this. Every entry says what the thing is, why doctors use it and what to expect, and offers questions the patient can tap to ask out loud, such as why do I need saline? It explains words, never the patient's own case, and every card points back to the care team. The top search finds a term and opens its card.

For a patient on a breathing tube or just out of surgery, the ICU mode opens phrases for breathing, the tube, pain from 0 to 10 and yes and no first, and Medical Words works from the bed too. Our guide to communicating with an ICU patient covers the rest of those days.