1. (noun) a measuring instrument for measuring the angle of magnetic dip (as from an airplane)

• dip circle

2. (noun) an instrument used by surveyors in order to measure an angle of inclination or elevation

• clinometer

1. (noun) a measuring instrument for measuring the angle of magnetic dip (as from an airplane)

• aeroplane
• airplane
• plane

1. (noun) an instrument showing the angle that an aircraft makes with the horizon

• navigational instrument

2. (noun) a measuring instrument for measuring the angle of magnetic dip (as from an airplane)

• measuring device
• measuring instrument
• measuring system

3. (noun) an instrument used by surveyors in order to measure an angle of inclination or elevation

• surveying instrument
• surveyor's instrument