How we change what others think, feel, believe and do
This is the use of an associated item to represent something. Thus:
Let me see thy righteous spirit!
We're out here, looking for the big cats.
For dust thou art, and unto dust shalt thou return.
By representing one thing as another thing, the listener has to pause and think hard about the association, especially when it is tenuous and conceptual, as synecdoche may be.
Synecdoche is a broader term than metonymy, which deals in nouns and more direct connection. Synecdoche deals in ideas as well.
Thus, for example, metonymy may used 'head' or even 'crown' to represent 'king'. Synecdoche could use 'country' or 'spirit'.
My lord, oh spirit of the nation!
Classification: Meaning, Substitution