What is the meaning of the phrase a "A woman without a man is like a fish without a bicycle"? Where does it come from? Why do we use the indefinite article before "man" and "woman" in this sentence?
It is in fact "A woman needs a man like a fish needs a bicycle".
It's an aphorism so "a" indicates unspecificity.
Have you ever seen a fish on a bicycle? It is the last thing it needs. So the aphorism implies women can exist quite well without men.
The alteration in the saying makes it meaningless.