De*cus"sate (?), *v. t.* [*imp. &
p. p.* __Decussated__; *p. pr. & vb. n.*
__Decussating__.] [L. *decussatus*, p. p. of *decussare*
to cross like an X, fr. *decussis* (orig. equiv. to *decem
asses*) the number ten, which the Romans represented by X.]
To cross at an acute angle; to cut or divide in the form of X;
to intersect; -- said of lines in geometrical figures, rays of light,
nerves, etc.

{ De*cus"sate (?), De*cus"sa*ted (?), }
*a.* **1.** Crossed;
intersected.

**2.** *(Bot.)* Growing in pairs, each of
which is at right angles to the next pair above or below; as,
*decussated* leaves or branches.

**3.** *(Rhet.)* Consisting of two rising
and two falling clauses, placed in alternate opposition to each
other; as, a *decussated* period.