unintentional
adj. B2 Upper Intermediate US //ˌənɪnˈtɛnʃənəɫ// UK //ˌʌnɪntˈɛnʃənəl// un·in·ten·tion·al
adj. done or happening by accident, not because you planned it. You use this to describe mistakes or surprises that you did not mean to cause.
adj. not done with purpose or intent; occurring without deliberate planning. Often used to qualify negative outcomes or errors to mitigate blame.
I am sorry for the unintentional mistake on the report.
The comedian's joke caused some unintentional offense among the audience members who took it literally.
While the policy change was designed to improve efficiency, it had the unintentional consequence of alienating the company's most loyal long-term clients.
From un- + intentional.
Usage
Typically used attributively before a noun; often paired with words like 'mistake', 'harm', or 'consequence'.