A clinical thermometer is a thermometer which is designed for clinical use in humans or animals. There are a number of considerations integrated into the design of clinical thermometers, including the need to reduce the risk of cross-contamination between patients. Many drug stores carry clinical thermometers which are designed for home use by people who want to be able to monitor their temperature. These products are also available from medical supply catalogs.
Historically, clinical thermometers were made with mercury, but today mercury thermometers are rarely seen in clinical use. The issue with a mercury clinical thermometer is that the thermometer can break, spilling mercury and posing a risk of human or animal health. Such thermometers can also be difficult to use, as they need to be held in place for several minutes, and they need to be swung to reset, as the thermometer is designed to hold the mercury in place once a maximum temperature has been reached so that the thermometer can be taken out for an accurate reading.