Thermohydrometer is a scientific instrument used for measuring temperature and humidity level of a particular area. However, there are several synonyms that people use quite commonly nowadays. Firstly, the term hygrometer is popular for measuring humidity levels. Secondly, the term thermometer is commonly used for measuring temperature in the atmosphere. Thirdly, the term thermo-hygrometer is a combination of both, used to measure both temperature and humidity at the same time. Additionally, a psychrometer is used for measuring humidity level by using two thermometers. Lastly, a digital thermometer with a humidity sensor is also used for measuring both temperature and humidity. All of these synonyms are used in a variety of scientific and domestic applications, making their use quite widespread.