40 Medical Words in English Every Patient Should Know [2026]

Understanding a doctor or a pharmacist in the UK asks for a specific set of words that general English courses rarely teach. You can be fluent in everyday conversation and still freeze when a nurse asks about your symptoms or a pharmacist explains a dosage. The vocabulary is narrow but high stakes, because getting it wrong can mean the wrong medicine or a missed instruction.

This guide lists 40 medical words grouped by the three moments where you need them most: describing your symptoms, understanding a diagnosis, and collecting a prescription. Each word has a plain definition and a sentence a patient could really say. Along the way it flags the everyday word British patients use when the formal medical term feels too technical. For the more technical language a clinician uses rather than a patient, our guide to medical English vocabulary goes further.

Describing your symptoms

This is where the appointment starts, and where a patient most needs to be clear.

1. symptom: a sign that something is wrong. My main symptom is a headache that will not go away.
2. ache: a dull, continuous pain. I have an ache in my lower back.
3. sore: painful when touched or used. My throat is really sore.
4. stiff: hard to move. My neck has been stiff since yesterday.
5. dizzy: feeling that you might fall or faint. I feel dizzy when I stand up quickly.
6. nausea: the feeling that you are going to be sick. The tablets gave me nausea.
7. rash: red, irritated skin. A rash appeared on my arm this morning.
8. swollen: larger than normal because of injury or illness. My ankle is swollen.
9. bruise: a dark mark on the skin after a knock. I have a bruise on my knee.
10. shortness of breath: difficulty breathing. I get shortness of breath when I climb stairs.
11. fatigue: extreme tiredness. The main problem is constant fatigue.
12. numb: with no feeling. My fingers went numb in the cold.
13. tender: sore when pressed. The area around the cut is tender.

British patients often say "I feel rough" or "I feel under the weather" for a general sense of illness before they get to the specific symptom.

Understanding a diagnosis

Once you have described the problem, these are the words that come back to you.

14. diagnosis: the doctor's decision about what is wrong. The diagnosis was a mild chest infection.
15. condition: a health problem, often a lasting one. She manages her condition with medication.
16. infection: illness caused by bacteria or a virus. You have an ear infection.
17. inflammation: swelling and redness inside the body. The scan showed inflammation in the joint.
18. chronic: lasting a long time. He has chronic back pain.
19. acute: severe and sudden. This is an acute reaction, not a long-term problem.
20. referral: being sent to a specialist. I am giving you a referral to a dermatologist.
21. specialist: a doctor who focuses on one area. The specialist will look at your knee.
22. scan: a detailed image of inside the body. We need a scan of your shoulder.
23. blood test: a test on a sample of your blood. The blood test came back normal.
24. GP: general practitioner, your local family doctor. Speak to your GP first.
25. A and E: accident and emergency, the hospital department for urgent cases. Go straight to A and E if it gets worse.
26. appointment: a booked time to see a doctor. I have an appointment on Thursday.

The letters GP and A and E are used far more in Britain than the full phrases, so it is worth recognising them by sound.

Collecting a prescription

The last step usually happens at a pharmacy, and it has its own vocabulary.

27. prescription: a doctor's written order for medicine. Take this prescription to the pharmacy.
28. pharmacy: the shop that dispenses medicine, also called the chemist. The pharmacy is open until six.
29. pharmacist: the professional who prepares your medicine. Ask the pharmacist about side effects.
30. dosage: how much medicine to take and how often. Follow the dosage on the label.
31. tablet: a small, solid piece of medicine. Take one tablet twice a day.
32. capsule: a small case containing medicine. Swallow the capsule whole.
33. painkiller: medicine that reduces pain. You can buy this painkiller without a prescription.
34. antibiotics: medicine that fights bacterial infection. Finish the whole course of antibiotics.
35. course: the full set of doses you must complete. Do not stop the course early.
36. side effect: an unwanted result of a medicine. Drowsiness is a common side effect.
37. dose: a single amount of medicine. Did you take your morning dose?
38. repeat prescription: a renewal you can collect without a new appointment. I need a repeat prescription for my inhaler.
39. over the counter: medicine you can buy without a prescription. This is available over the counter.
40. allergy: a bad reaction to something. Tell the pharmacist about any allergy you have.

For medicine itself, British patients often just say "tablets" for almost anything solid, and "my prescription" for the medicine as a whole, even when the formal word would be more precise. These words are just as useful when illness strikes away from home, so they sit naturally alongside our guide to travel words in English.

Knowing these words turns a stressful appointment into a manageable one. A CEFR level is really a description of what you can do in English, not just a score, so a free English level test will show you which real situations, a doctor's appointment among them, you can already handle on your own.