SYMBOL

Definition : an object or anything that stands for something else that's more abstract.


Example : 
O Rose, thou art sick. 
The invisible worm 
That flies in the night 
In the howling storm 




[Chinese characters is another great example for symbolism.]


Significance : Try to be careful with symbol because sometimes the readers won't understand what's your nonsense saying is all about. Symbolism is partly like an extended metaphor but for symbolism, we don't compare. In symbolism, the words we choose could mean more than what they mean. Words are more powerful than the picture because if we apply imagery for symbol, sometimes we won't get any clue.