What does the idiom 'to shed crocodile tears' mean?

Supposedly, when crocodiles swallow large chunks of meat, their eyes water -- thus, people started saying they cried when they ate you! If you cry "crocodile tears," you are not really crying, but only putting on a fake show of feeling sorry.
Crying/pretending to cry in order to deceive.
It refers to a person who pretends to care but really doesnt. After all a crocodile would never care or be sad for it's prey.

since crocodiles are not know to cry - means shedding fake tears