The term "aneroidograph" refers to a barometer that measures air pressure without using any liquid. While the word is specific to this type of device, there are several synonyms that can be used to describe it. One common synonym is "digital barometer," which provides an electronic readout of air pressure. Another synonym is "mercury-free barometer," as aneroidographs do not use mercury and therefore have become a popular alternative. Additionally, the term "mechanical barometer" can be used, as aneroidographs rely on a mechanical system to measure pressure changes. Finally, the term "non-liquid barometer" could be used to describe this type of instrument.