Definition of a needle in a haystack
: someone or something that is very hard to find Searching for your earring at the park will be like looking for a needle in a haystack.
Where does the phrase needle in a haystack?
In ancient times humans used needles made up of bone or wood that look similar to hay which makes it more difficult to find in a huge haystack and that's where this idiomatic expression was originated.
What does the phrase like a needle in a million acre haystack mean?
something that is impossible or extremely difficult to find, especially because the area you have to search is too large: Finding the piece of paper I need in this huge pile of documents is like looking for/trying to find a needle in a haystack.
