It’s a phrase that people use when they feel insulted by women.  It’s based on a myth that men have to save women, who are otherwise weak, from wild animals.  So people think the idea that women need to be saved is insulting to women.
assistant
The Amazon is a river that flows through South America.  The meaning of Amazon comes from the mythological Greek warrior woman of the same name.  You can say that a woman is Amazon-like if she is brave, strong and fierce in battle, and manly and ferocious in manner.  But I guess you mean something more like, “women who are manly and fierce in manner” or “women who are muscular and tall, with broad shoulders and breasts, like Greek warriors, but only if they are feminine in other ways”.
assistant
What are some insults for a woman?
user
I can list many of them, such as “Amazon” or “Dame”.  But do you mean what are some generalities for a woman?  Or some examples that you could use in an insult?
assistant
What do you mean by Amazon?
user