English Word · Advanced
backstaff
An early navigational instrument for measuring the altitude of the sun and hence calculating latitude
Pronunciation: say backstaff
Meaning
An obsolete navigational instrument used to measure the altitude of the sun by observing its shadow, allowing for the calculation of latitude.
Example
The navigator used a backstaff to determine the ship's position by measuring the sun's altitude.
The navigator used a backstaff to determine the ship's position by measuring the sun's altitude.
Practice tips
- Practice backstaff out loud — read the pronunciation guide above and repeat.
- Use it in your own sentence today; reuse beats rereading.
- Pay attention to context: this English word is for advanced-level learners.