Temporary chemical transformation
of a reactive group into a group that does not react under conditions where the non-protected group reacts.
For example, trimethylsilylation is a typical transformation
used to protect reactive functional groups, such as hydroxy or amino groups, from their reaction with growing anionic species in anionic polymerization
PAC, 2004, 76, 889
(Definitions of terms relating to reactions of polymers and to functional polymeric materials (IUPAC Recommendations 2003))
on page 894
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8. doi:10.1351/goldbook