The worm turns

Hi,

I know that the idiom, the worm has turned, originates from the phrase, "the smallest worm will turn, being trodden on." I know the idiom's current use.

I don't understand the meaning of the origin. What does it mean for a worm to turn? Please help me out, if you can.

Jennie

It means that the worm will turn ON its attacker, in the sense of counterattacking, fighting back. I don't think worms really do that. The whole phrase is a metaphor about people. It just happens to star a worm.