1. A thorough and meticulous examination or inquiry into something, conducted with attention to detail and caution
The police conducted a careful investigation into the crime.
A polícia realizou uma investigação cuidadosa sobre o crime.
2. A systematic study or research process performed with prudence and diligence
The scientist's careful investigation revealed new findings about the disease.
A investigação cuidadosa do cientista revelou novas descobertas sobre a doença.