v.
 (cancels, cancelling, cancelled; US also cancels, canceling, canceled)
    - decide that (a planned event) will not take place. 
▸annul or revoke:
 his visa had been cancelled.
 - mark or tear (a ticket or stamp) to show that it has been used or invalidated.
 - 
(often cancel something out)
 (of a factor or circumstance) neutralize or negate the effect of (another).
 - Mathematics  delete (an equal factor) from both sides of an equation or from the numerator and denominator of a fraction.
 
n.
   - a mark made on a postage stamp to show that it has been used.
 - Printing  a new page or section inserted in a book to replace the original text.
 - US (in music) a natural sign (♮).
 
 
  Derivative
  
    - cancellation n.
  - canceller n.
 
   
  Etymology
  ME: from OFr. canceller, from L. cancellare, from cancelli ‘crossbars’.