A border or edge covered with a scalloped or ornamental design; also, an embroidered border or festoon (archaic).
From French 'feston,' related to 'festonne' (edged with a design), which may derive from Italian 'festone' or from the concept of a looped or scalloped border resembling a chain or garland.
Seamstresses knew 'feston' for centuries as a specific decorative stitch that creates those pretty scalloped edges, but as sewing became less common, the word faded into obscurity.
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