1. in a manner free from bias, prejudice, or selfish motives; impartially
The judge ruled disinterestedly on the case, considering only the facts and the law.
O juiz julgou desinteressadamente o caso, considerando apenas os fatos e a lei.
2. without personal involvement or concern; indifferently
He listened disinterestedly to their complaints.
Ele ouviu desinteressadamente as reclamações deles.