Alidade

2 definitions found

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  Alidade \Al"i*dade\, n. [LL. alidada, alhidada, fr. Ar.
     al-'id[=a]da a sort of rule: cf. F. alidade.]
     The portion of a graduated instrument, as a quadrant or
     astrolabe, carrying the sights or telescope, and showing the
     degrees cut off on the arc of the instrument --Whewell.
     [1913 Webster]



From WordNet (r) 2.0 [wn]:

  alidade
       n 1: surveying instrument consisting of the upper movable part of
            a theodolite including the telescope and its attachments
            [syn: {alidad}]
       2: surveying instrument used with a plane table for drawing
          lines of sight on a distant object and for measuring
          angles [syn: {alidad}]