What does hygrograph mean?
A hygrograph is an instrument used to record changes in humidity, especially the relative humidity of the atmosphere. Unlike a hygrometer, which provides a reading at a particular moment, a hygrograph produces a continuous record, often on a rotating drum or chart, that allows moisture trends to be examined over hours or days. The word can also denote that record itself. Hygrographs are associated with meteorology, museums, laboratories, and other settings where changes in atmospheric conditions must be monitored. The term is more specialized than the everyday expression humidity chart and is chiefly encountered in technical, scientific, and historical writing. Its principal distinction is temporal: a hygrometer answers how humid it is now, whereas a hygrograph shows how humidity has changed. Although electronic data loggers now perform comparable recording functions, hygrographs remain important in the history of atmospheric measurement and in the study of historic environmental records.
nounAn instrument that continuously records changes in atmospheric humidity, typically on a chart. The term can also refer to the chart or graphical record produced by such an instrument.
- An instrument that records changes in atmospheric humidity.
- A chart or graphical record produced by such an instrument.
"The hygrograph traced a steady rise in humidity throughout the night."
"The hygrograph shows a sharp increase in humidity before the storm."
"His grandfather kept the hygrograph beside the garden's barometer."
Used when referring to multiple instruments or humidity records.
"The laboratory acquired hygrographs for several monitored storage rooms."
A hygrograph does more than measure moisture: it leaves a visual story of how humidity changes over time.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does hygrograph come from?
Hygrograph combines the combining form hygro-, derived from Greek hygros, meaning “moist” or “wet,” with graph, from Greek graphē, meaning “writing” or “a record.” The combination therefore describes an instrument or record for writing down changes in moisture. Its related vocabulary includes hygrometer, an instrument for measuring humidity, and hygroscopic, meaning “attracting or absorbing moisture.”
Related word forms
How hygrograph is actually used
This is primarily a technical or historical term. In meteorological and scientific contexts, it usually denotes the recording instrument, while the resulting chart is described as a hygrograph record or trace.
Easily confused with hygrograph
A hygrometer measures humidity at a given moment, whereas a hygrograph records changes in humidity over a period of time.