unintentional

Adjective

• not done with purpose or intent
  • an unintended slight
    
  • an unintentional pun
    
  • the offense was unintentional
    
  • an unwitting mistake may be overlooked
    

• without deliberate intent
  • my heart with unwilled love grew warm- George Macdonald
    

Related words

• Synonyms: 
  unplanned , unwitting , unwilled