3.3.5 Synecdoche
A synecdoche is a device which the writer/poet uses to signify the whole, such as using a part of the body to mean the whole person, for example, the head or the hand. It is a means of substituting the particular for the general and so enables the writer to make a more specific statement
Example:
Perhaps in this neglected spot is laid
Some heart once pregnant with celestial fire;
Hands that the rod of empire might have swayed,
Or waked to ecstasy the living lyre.
There are two synecdoches in the above extract with the particular use of "heart" and "hand" to represent the unknown person buried in the graveyard. He could have been a great statesman or even a poet! The use of the synecdoche enables Gray to speculate about this person.