involuntarily
🇺🇸
/ɪnˌvɑːlənˈterəli/
🇬🇧
/ɪnˈvɒləntrəli/
without intending to or being able to control it
She shuddered involuntarily when she heard the loud noise.
without the person wanting it to happen
He was involuntarily committed to a mental institution.