(1) Parallelism of fibres, usually as a result of a combing or attenuating action on fibre assemblies causing the fibres to lie substantially parallel to the axis of the web or strand
(2) A predominant direction of linear molecules in the fine structure of fibres.
Note 1: In man-made fibres orientation is usually parallel to the fibre axis as a result of extrusion stretching, or drawing. In natural fibres the predominant direction is determined during growth, for example a helix around the fibre axis in cotton.
Note 2: Unoriented structures are those in which orientation is absent. Disoriented structures are those in which orientation has been reduced or eliminated as a result of a disrupting treatment
Textile Resource (http://www.textile.org.uk)