selvedge
/ˈsɛlvɪdʒ
/(chiefly North American also selvage)
noun
1An edge produced on woven fabric during manufacture that prevents it from unravelling.An act in effect between 1774 and 1811 required that blue threads be woven into the selvages of cotton cloth intended for export if a refund of the tax on printed cotton was to be claimed....
- In other cases, a laser was used to create decorative motifs on fabrics, or to cut fabric fringes along the selvage.
- For the neatest finish, cut strips along the selvage using the selvage for the seam allowance.
2 Geology A zone of altered rock, especially volcanic glass, at the edge of a rock mass.This type of migmatite is characterized by discrete millimetre - to centimetre-scale discontinuous granitic layers separated by high-grade metamorphic host rock and dark selvages (mesosome)....
- Likely all of these factors played some role in initiating beryl precipitation, particularly where mineralization is contained within highly altered vein selvages.
- The fine-grained selvage called a chilled margin, formed in a younger rock in contact with an older rock, has already been mentioned.
Origin
Late Middle English: from an alteration of self + edge, on the pattern of early modern Dutch selfegghe. The geological term dates from the 1930s.