ramus communicans
nounMedical Definition of ramus communicans
: any of the bundles of nerve fibers connecting a sympathetic ganglion with a spinal nerve and being divided into two kinds:
a
: one consisting of myelinated preganglionic fibers
— called also white ramus, white ramus communicans
b
: one consisting of unmyelinated postganglionic fibers
— called also gray ramus, gray ramus communicans