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

collimate \col"limate\, v. t. imp.  p. p. collimated; p. p.
    vb. n. collimating. see collimation. physics 
   astron.
   to render parallel to a certain line or direction; to bring
   into the same line, as the axes of telescopes, etc.; to
   render parallel, as rays of light.
   1913 webster

   collimating eyepiece, an eyepiece with a diagonal reflector
      for illumination, used to determine the error of
      collimation in a transit instrument by observing the image
      of a cross wire reflected from mercury, and comparing its
      position in the field with that of the same wire seen
      directly.

   collimating lens optics, a lens used for producing
      parallel rays of light.
      1913 webster
see also:
collimated collimating collimation collimating eyepiece collimating lens 

[2] : WordNet (r) 2.0

collimate
     v 1: make or place parallel to something; "they paralleled the
          ditch to the highway" syn: parallel
     2: adjust the line of sight of an optical instrument
see also:
parallel 

Collimate >> C Words
Collimate, definition of term: Collimate
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