A term I have seen only in anatomy books.
decussate
vt., vi.
3sat#ed, 3sat#ing 5< L decussatus, pp. of decussare, to cross in the form of an X < decussis, the figure ten (X) < decem, TEN6 to cross or cut so as to form an X; intersect
adj.
1 forming an X; decussated
2 Bot. arranged in pairs growing at right angles to those above and below: said of leaves or branches
de[cus4sate[ly
adv.