Lignin
Definition
A complex chemical compound most commonly found in wood, and an integral part of the secondary cell walls of plants and some algae.
Source
Glossary. M.S. Ashton et al. (eds.), Managing Forest Carbon in a Changing Climate,DOI 10.1007/978-94-007-2232-3, © Springer Science + Business Media B.V. 2012
Alternative definition
A substance in wood which binds its fibres together and reinforces its structure. Lignin is removed in the manufacture of chemical pulp.
Alternative source
TRG(121)/GICM, FAO, 2005. Glossary of Paper Terms, Institute of Paper, Printing and Publishing, UK, 2005 (http://www.ip3.org.uk/glossary.htm).2005.