n. pl. ni·el·li (-ĕlē) or ni·el·los
1. Any of several black metallic alloys of sulfur with copper, silver, or lead, used to fill an incised design on the surface of another metal.
2. A surface or object decorated with one of these alloys.
3. The art or process of ornamenting metal surfaces with one of these alloys.
tr.v. ni·el·loed, ni·el·lo·ing, ni·el·los
To decorate or inlay with niello.
[Italian, from Medieval Latin nigellum, from neuter of Latin nigellus, diminutive of niger, black; see nekw-t- in the Appendix of Indo-European roots.]
(click for a larger image)niello
sterling silver and niello
shield-shaped shoe buckle
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2019 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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