(1) Descriptive of yarns spun entirely from flax fibres
(2) Descriptive of fabrics woven from linen yarns
(3) Descriptive of articles which, apart from adornments, are made of yarns spun from flax
Note: Despite some usage of this term in non-technical circles as a generic one, e.g. linen department, baby linen, household linen, it does not apply to individual articles that do not comply with the definition.
see also Irish Linen
Textile Resource (http://www.textile.org.uk)