(n.) An instrument to indicate the state of the atmosphere, especially changes of atmospheric pressure, and hence changes of weather, as a barometer or baroscope.

aerological instrument aneroid barometer aneroidograph barograph barometrograph canon check criterion degree feeler gauge glass graduated scale hurricane-hunter aircraft hygrometer measure model norm parameter pattern pilot balloon probe quantity radiosonde random sample reading readout recording barometer rule sample scale sound sounder standard straw vote test touchstone trial balloon type vacuometer value weather balloon weather instrument weather satellite weather vane weathercock weatherglass yardstick