A crystalline domain usually limited by well-defined boundaries.
Notes: - Polymer crystals frequently do not display the perfection that is usual for low-molar-mass substances.
- Twinned polymer crystals are, sometimes, erroneously referred to as 'crystals'.
- Polymer crystals that can be manipulated individually are often called (polymer) single crystals. A single crystal may contain different fold domains.
Source:
Purple Book, 1st ed., p. 76 (http://old.iupac.org/publications/books/author/metanomski.html)