What does the building decorating term rechampis mean in French?

The French verb Rechampir (also spelled réchampir) means to make a mold or other ornament, stand out from the background on which it stands, by outlining its contour, or by using a different colour that the one used for the background proper. Rechampi is the noun derived from the verb, indicating the decor which has been treated in that way, and most often the thin line of paint of an outline.

The "pinceau à rechampir" is a kind of round, but somewhat pointed brush.