👉 The term "litmus" is a device used in medicine to determine whether an individual has a certain condition or disease. It consists of a thin, metal strip that can be put into the mouth and then placed against the tongue for a few seconds. If the person's tongue feels red or warm after putting the litmus strip against their tongue, it means they have the condition being tested. The test is usually done to check if someone has any type of infection in their mouth.
litmus