v.
  
/
ɪkˈskjuːz, 
ɛk-/
  
- try or serve to justify (a fault or offence); mitigate. 
▸forgive (a fault or offence, or a person committing one).
 - release from a duty or requirement. 
▸(used in polite formulas) allow to leave a room or gathering.
 ▸
(excuse oneself)
 say politely that one is leaving.
 
n.
  
/
ɪkˈskjuːs, 
ɛk-/
   
- a defence or justification of a fault or offence.
 - something said to conceal the real reason for an action.
 - 
(an excuse for)
 informal a poor or inadequate example of.
 
 
  Phrase
  
  Derivative
  
    - excusable adj.
  - excusably adv.
  - excusatory adj.
 
   
  Etymology
  ME: from OFr. escuser (v.), from L. excusare ‘to free from blame’, from ex- ‘out’ + causa ‘accusation, cause’.