1. In a manner not intended or desired; without conscious will or deliberate choice
He involuntarily flinched at the sudden noise.
Ele se encolheu involuntariamente com o barulho repentino.
2. Against one's will; without voluntary consent or participation
She was involuntarily transferred to another department.
Ela foi transferida involuntariamente para outro departamento.
3. By reflex or automatic response, not through conscious effort
He involuntarily held his breath underwater.
Ele prendeu a respiração involuntariamente debaixo d'água.