Definitions for macrocyclicˌmæk roʊˈsaɪ klɪk, -ˈsɪk lɪk
Random House Webster's College Dictionary
mac•ro•cy•clicˌmæk roʊˈsaɪ klɪk, -ˈsɪk lɪk(adj.)
having a ring structure consisting of more than 12 atoms.
Origin of macrocyclic:
having a closed ring of more than about twelve atoms
of, or relating to a macrocycle