Curtain tie-back

Within the field of interior decoration, tie-backs made of fabric are classified as a kind of "soft furnishing" (along with other fabric-based décor such as pillows, valances, towels, blankets, mattresses, bed skirts, bedspreads, jabots, and shower and window curtains) while those made out of wood, metal, or glass are considered "window hardware" (along with curtain rods, cornices, latches, hinges, push bars, and handles).

A structured tie-back consists of a single short U-shaped strip of fabric held flat by a piece of interfacing.

[1] A ruched tie-back consists of a roll of interfacing covered with a gathered tube of fabric.

The length of rope beyond the cinch bead is referred to as the embrace and must be long enough to comfortably but securely hold the curtain.

The width of the knob serves to hold the curtain from spilling back into the window.