chiastic:
1. of or relating
to the intersection of opposites:
thesis/antithesis
convergence/divergence
synthesis/analysis
yin/yang
life/death
&c.
2. of or relating to chiasmus or chiasma
3. repetition of ideas or grammatical structures (not identical words) in inverted order
4. repetition of words, phrases, letters or numbers in inverted order
want more on this madness? search google or make up your own definition.