For
woven textile
Textile is an umbrella term that includes various fiber-based materials, including fibers, yarns, filaments, threads, different fabric types, etc. At first, the word "textiles" only referred to woven fabrics. However, weaving is not t ...
s, grain refers to the orientation of the
weft and warp threads. The three named grains are straight grain, cross grain, and the bias grain. In sewing, a pattern piece can be cut from fabric in any orientation, and the chosen grain or orientation will affect the way the fabric hangs and stretches and thus the fit of a garment. Generally speaking a piece is said to be cut on a particular grain when the longest part of the pattern or the main seams of the finished piece are aligned with that grain. Non-woven materials such as
felt
Felt is a textile material that is produced by matting, condensing and pressing fibers together. Felt can be made of natural fibers such as wool or animal fur, or from synthetic fibers such as petroleum-based acrylic or acrylonitrile or w ...
,
interfacing or
leather
Leather is a strong, flexible and durable material obtained from the tanning, or chemical treatment, of animal skins and hides to prevent decay. The most common leathers come from cattle, sheep, goats, equine animals, buffalo, pigs and ho ...
do not have a grain.
Straight grain
The straight grain is oriented parallel with the warp threads and the
selvedge. The straight grain typically has less stretch than the crossgrain since the warp threads will be pulled tighter than the weft during weaving. Most garments are cut with the straight grain oriented top to bottom.
[Howard, Pamela. "For woven fabrics, it's important to go with the grain". Threads (Taunton Press) April/May 2005.]
Cross grain
The cross grain runs perpendicular to the selvedge and parallel to the weft threads. The cross grain generally has more stretch than the straight grain since the weft threads are generally looser than the warp during weaving. Most garments (like
pants
Trousers (British English), slacks, or pants are an item of clothing worn from the waist to anywhere between the knees and the ankles, covering both legs separately (rather than with cloth extending across both legs as in robes, skirts, and ...
or
shirt
A shirt is a cloth garment for the upper body (from the neck to the waist).
Originally an undergarment worn exclusively by men, it has become, in American English, a catch-all term for a broad variety of upper-body garments and undergarments. I ...
s) are cut on the straight grain with the cross grain parallel with the floor when the wearer is standing. This allows more stretch through the width of the garment, such as in a pants leg which needs more circum