testingfluid
nounUK /ˈtɛstɪŋˌfluːɪd/
US /ˈtɛstɪŋˌfluːɪd/
A special liquid used to check if something works or is safe.
The scientist put a drop of testing fluid on the strip to see if the water was clean.
RELATED WORDS
OTHER MEANINGS
2. A liquid made in a lab to help find out what is wrong with a machine.
The mechanic used a testing fluid to find the leak in the engine.
3. Any liquid used during an experiment to compare results.
Each group received the same testing fluid so their results could be compared.
4. A fluid used to check the quality of a product before it is sold.
The factory adds a testing fluid to every batch to make sure the toy paint is safe.