blanch vb
1 to remove colour from, or (of colour) to be removed; whiten; fade
the sun blanched the carpet
2 to become or cause to become pale, as with sickness or fear
3 to plunge tomatoes, nuts, etc., into boiling water to loosen the skin
4 to plunge (meat, green vegetables, etc.) in boiling water or bring to the boil in water in order to whiten, preserve the natural colour, or reduce or remove a bitter or salty taste
5 to cause (celery, chicory, etc.) to grow free of chlorophyll by the exclusion of sunlight
6 (Metallurgy) to whiten (a metal), usually by treating it with an acid or by coating it with tin
7 to attempt to conceal something
(C14: from Old French blanchir from blanc white; see blank)