“+ noun
Etymology: International Scientific Vocabulary macr- + molecule
: a very large molecule (as of a protein, cellulose, rubber, or other natural or synthetic high polymer)
possess more reliable information on the structure of atoms and small molecules than on the structure of colloidal particles and macromolecules — Physics Today
macromolecules with a diameter of about 100 A (.10 -5 mm) … can be seen in electron micrographs — Felix Haurowitz