|n. pl.||1.||(Zool.) A division of Hydroidea, including those genera that secrete a stony coral, as Millepora and Stylaster. Two forms of zooids in life project from small pores in the coral and resemble those of other hydroids. See Millepora.|
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.