Snake-like movement of a polymer chain in a semi-dilute or concentrated solution or bulk amorphous polymer through the hypothetical tube created by neighbouring chains.
Source: PAC, 2015, 87, 71. (Definitions of terms relating to individual macromolecules, macromolecular assemblies, polymer solutions, and amorphous bulk polymers (IUPAC Recommendations 2014)) on page 105 [Terms] [Paper]