Etymology Likely a nominalization of Middle English stencellen (“to garnish with bright hues”), borrowed from Middle French estinceller (“to glisten”), from Old French estenceler (“to spark”), from Old French estencele (“spark”), from Vulgar Latin *stincilla, from metathesis of Latin scintilla (“spark”). The verb is from the noun.
1
A thin sheet, either perforated or using some other technique, with which a pattern may be produced upon a surface; a utensil that contains a perforated sheet.
You do not necessarily need to have a stencil brush to paint over a stencil.2015, Margaret Peot, Stencil Craft: Techniques for Fashion, Art and Home, Penguin, →ISBN:
2
A pattern produced using such a utensil.
In 2013 a damaged stencil of a rat and an image of a girl hugging a bomb were painted over on the walls of a Fitzroy church by the building owner’s father-in-law, who tried to help out by painting the building while house sitting. He did not know the significance of the stencils.2016 July 11, Calla Wahlquist, “Banksy stencils destroyed by construction workers in Melbourne”, in The Guardian:
Etymology Likely a nominalization of Middle English stencellen (“to garnish with bright hues”), borrowed from Middle French estinceller (“to glisten”), from Old French estenceler (“to spark”), from Old French estencele (“spark”), from Vulgar Latin *stincilla, from metathesis of Latin scintilla (“spark”). The verb is from the noun.
1
To print with a stencil.
Stencilled letters were used for words and phrases, as well as for captions for some of his stencil “prints,” print being used in the sense of a multicolor woodcut.2015, William Addison Dwiggins, edited by Dorothy Abbe, Stencilled Ornament and Illustration, Chronicle Books, →ISBN, page 53: