Tracery /(?)/

pl. Traceries

1. Ornamental work with rambled lines. (Arch.)
2. A similar decoration in some styles of vaulting, the ribs of the vault giving off the minor bars of which the tracery is composed.
3. A tracing of lines; a system of lines produced by, or as if by, tracing, esp. when interweaving or branching out in ornamental or graceful figures.