Meaning of the word "test positive/negative for" in English

What does "test positive/negative for" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

test positive/negative for

US /test ˈpɑː.zə.t̬ɪv/ˈneɡ.ə.t̬ɪv fɔːr/
UK /test ˈpɒz.ə.tɪv/ˈneɡ.ə.tɪv fɔː/
"test positive/negative for" picture

Phrase

to show a positive or negative result in a medical or chemical test for a specific substance or disease

Example:
The athlete tested positive for a banned substance.
Thankfully, she tested negative for the virus.