The term potometer refers to an instrument used to measure the rate of transpiration in plants. Some synonyms that can be used in place of potometer include transpirometer, evapotranspirometer, and plant transpiration meter. Other potential options could include water loss meter, plant moisture gauge, or plant hydrometer. In general, the term potometer is the most widely used and recognized term for this type of instrument, as it has been in use for many years in the scientific community. However, there are various alternatives that can be used depending on the context or specific application.