A meat thermometer is a device used to measure the internal temperature of cooked or raw meat in order to determine if it has reached a safe level for consumption. It typically consists of a long, thin probe that can be inserted into the thickest part of the meat, and an indicator on the outside that displays the current temperature. The thermometer helps ensure that food is properly cooked through, preventing illnesses such as salmonella or E. coli from contaminated undercooked meat.