Definify.com
Webster 1913 Edition
Backstaff
Back′staffˊ
,Noun.
An instrument formerly used for taking the altitude of the heavenly bodies, but now superseded by the quadrant and sextant; – so called because the observer turned his back to the body observed.
A
backstairs
influence. Burke.
Female caprice and
backstair
influence. Trevelyan.
Webster 1828 Edition
Backstaff
BACK'STAFF
,Noun.
A quadrant; an instrument for taking the sun's altitude at sea; called also, from its inventor, Davis's quadrant.
Definition 2024
backstaff
backstaff
English
Noun
backstaff (plural backstaffs)
- (nautical) An early navigational instrument for measuring the altitude of the sun and hence calculating latitude