variometer
Concise Oxford English Dictionary © 2008 Oxford University Press:
variometer /ˌvɛːrɪˈɒmɪtə/
▶noun
- 1 a device for indicating an aircraft's rate of climb or descent.
- 2 Electronics a device whose total inductance can be varied.
- 3 an instrument for measuring variations in the earth's magnetic field.
'variometer' also found in these Oxford entries:

