ramus communicans

noun

ramus com·​mu·​ni·​cans -kə-ˈmyü-nə-ˌkanz 

plural rami communicantes -kə-ˌmyü-nə-ˈkan-ˌtēz 

: 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