spiro macromolecule

A double-strand macromolecule consisting of an uninterrupted sequence of rings, with adjacent rings having only one atom in common. Alternatively, a spiro macromolecule is a double-strand macromolecule with adjacent constitutional units joined to each other through three atoms, two on one side and one on the other side of each constitutional unit.
Source:
PAC, 1996, 68, 2287 (Glossary of basic terms in polymer science (IUPAC Recommendations 1996)) on page 2295