化验

Use it as a verb or a noun. Usually, you'll say 去化验 (go to get tested) or 化验单 (the test result sheet). You don't 'do' a 化验 like a chore. You 'undergo' it or 'send' something for it. If a doctor says you need a blood test, they will say 抽血化验. It’s very specific to laboratory settings. Don't use it for testing a new car or a phone.

You'll use this most often at the hospital or a clinic. If you're feeling under the weather and the doctor wants to be sure, they'll send you to the 化验室 (lab). It’s also used in industrial settings for testing water quality or food safety. If you're texting a friend why you're late, you might say you're waiting for 化验结果 (test results).

Never use 化验 for a school exam; that is 考试. Don't use it for 'trying out' a new hobby or a piece of cake. For those, use 尝试 or 试一下. Also, don't use it for a general physical exam. That is 体检. 化验 is only for the part involving chemicals and samples. Using it for a math test will make your teacher very confused!

In China, hospital visits are often 'one-stop shops.' You see the doctor, get a 化验单, go to the lab downstairs, and wait for the results. People are very used to the phrase 挂号、看病、化验 (register, see doctor, test). It’s a standard rhythm of life. Interestingly, the term feels very modern and scientific. It reflects China's shift toward Western medicine and rigorous laboratory standards over the last century.

化验员 is the lab technician. 化验单 is that little slip of paper you're terrified of losing. 血化验 is a blood test. 尿化验 is a urine test. If you want to be extra casual, you might just say 去验一下. But 化验 remains the most accurate term for anything involving a lab and a pipette.