Chiasmus

A rhetorical figure, named for the Greek letter chi (which looks like an "X"). The "X" suggests the crossing that characterizes the figure. Some examples:
Ask not what your country can do for you, but what you can do for your country.
We can see the chiasmus with "country" and "you" if we lay it out this way (in clumsy ASCII art, but I'm too lazy to work up a graphic):
 Ask not what your country can do for you,
                      \               /
                         \         /
                            \   /
                              X
                            /   \
                         /         \
                      /               \
	  but what you can do for your country.
Chiasmus doesn't have to be the same words: it's often the same parts of speech. Here's Milton:
Be still, thou waves, and thou deeps, peace. ???
???


From the Guide to Literary Terms by Jack Lynch.
Please send comments to jlynch@andromeda.rutgers.edu.
Note: This guide is still in the early stages of development. Bear with me.