- a black metallic substance, consisting of silver, copper, lead, and sulfur, with which an incised design or ground is filled to produce an ornamental effect on metal.
- ornamental work so produced.
- a specimen of such work.
- a print on paper made from an incised metal plate before the application of niello and associated especially with 15th-century Italy.
- to decorate by means of niello; treat with niello or by the niello process.
- a black compound of sulphur and silver, lead, or copper used to incise a design on a metal surface
- the process of decorating surfaces with niello
- a surface or object decorated with niello
- to decorate or treat with niello
