hydrocaulus

== English == === Etymology === From New Latin hydrocaulus, from hydro- +‎ Ancient Greek καυλός (kaulós, “stalk, stem”). === Noun === hydrocaulus (plural hydrocauli) (zoology) The hollow stem of a hydrozoan ==== Derived terms ==== hydrocauline === References === “hydrocaulus”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.