verb (v)

• make fine adjustments or divide into marked intervals for optimal measuring(verb.change)

  Example:
  Calibrate an instrument.
  

  Synonym:
  fine-tune, graduate
  

  source: wordnet30
• mark (the scale of a measuring instrument) so that it can be read in the desired units(verb.contact)

  Example:
  He calibrated the thermometer for the Celsius scale.
  

  source: wordnet30
• measure the caliber of(verb.cognition)

  Example:
  Calibrate a gun.
  

  source: wordnet30
• To ascertain the caliber of, as of a thermometer tube; also, more generally, to determine or rectify the graduation of, as of the various standards or graduated instruments.(verb)

  source: webster1913