Definition 1 of 2
Definition
The finished, woven border running lengthwise along each side of a roll of fabric, formed during weaving so the edge will not unravel. On aircraft covering fabrics, the selvage edge is used as a straight reference for cutting, aligning, and laying out fabric panels.
Plain English
The neat, tightly woven strip along the long edge of a roll of fabric that keeps it from fraying. It runs the full length of the roll on both sides.
Context Anchor
Seen in aircraft fabric covering, sewing, and repair instructions when laying out, trimming, or inspecting fabric.
Derivation
From the older English term 'self-edge' -- literally the edge that finishes itself during weaving. Knowing this helps you remember that the selvage is the edge the loom builds in, not one created by cutting.
Why Pilots Care
Mechanics and builders use the selvage edge as a straight, stable reference when cutting and aligning fabric panels. Working from the selvage helps keep the weave straight on the airframe, which matters for proper shrinkage, finish, and strength.
Analogy
It is like the finished side edge of a ribbon: it was made that way, so it resists coming apart better than a freshly cut end.
Intuition Check
Do not read “selvage edge” as just any edge of the fabric. It specifically means the finished factory edge made during weaving.
Example Sentence 1
He aligned the selvage edge of the covering fabric with the wing's trailing edge before making the first cut.
Example Sentence 2
Leaving the selvage edge intact along the trailing edge gave the fabric covering extra strength.