What is the meaning of the idiom 'A wild goose chase'?

• A wild goose chase (Idiom)
English Meaning: A foolish and hopeless search for or pursuit of something unattainable.
Bangla Meaning; অনর্থক প্রয়াস বা পরিশ্রম।
- If you are on a wild goose chase, you waste a lot of time searching for something that you have little chance of finding, because you have been given incorrect information.

• Example sentence:
- Physicists searching for the hypothetical particle may be on a wild goose chase.
- Harry wondered if Potts had deliberately sent him on a wild goose chase.

Source:
1. Oxford Learner's Dictionary.
2. Collins Dictionary.
3. Accessible Dictionary by Bangla Academy.