A sextant is an instrument used for measuring angles, for example between the sun and the horizon, so that the position of a ship or aeroplane can be calculated.
sextant in British English
(ˈsɛkstənt)
noun
1.
an optical instrument used in navigation and consisting of a telescope through which a sighting of a heavenly body is taken, with protractors for determining its angular distance above the horizon or from another heavenly body
2.
a sixth part of a circle having an arc which subtends an angle of 60°
Word origin
C17: from Latin sextāns one sixth of a unit
sextant in American English
(ˈsɛkstənt)
noun
an instrument used by navigators for measuring the angular distance of the sun, a star, etc. from the horizon, as in finding the position of a ship
Word origin
ModL sextans (gen. sextantis), arc of a sixth part of a circle < L, a sixth part < sextus, sixth
Examples of 'sextant' in a sentence
sextant
A whole generation of Coast Guard officers had learned the use of the sextant from this swarthy, overweight professional.