たしtashiかめるkameru
1.

To verify the truth or accuracy of something through direct observation or investigation.

2.

To confirm information or details by checking or cross-referencing with reliable sources.

3.

To ensure clarity and understanding by asking questions or seeking further information.

4.

To establish certainty about a situation or fact by investigating or questioning.

Example:

窓が閉まっているか確かめとけ。