1. the act or process of examining something carefully and thoroughly to discover facts or information
Usage: plural form of investigation; commonly used in academic, legal, and journalistic contexts
2. a formal or official examination conducted by authorities to determine the facts about an incident or allegation
Usage: often used in legal, police, or institutional contexts

Examples

• The police launched multiple investigations into the robbery.
• Scientific investigations require careful observation and documentation.
• The company conducted several investigations after the safety complaints.
• Journalists' investigations uncovered corruption in the government.
• The investigations revealed important new evidence in the case.
• Several ongoing investigations are examining the cause of the accident.