transitive verb

1. to make white; take color out of
2. to make pale
3. to bleach (endive, celery, etc.) by earthing up or covering so as to keep away light and improve the appearance, flavor, or tenderness
4. 1. to scald (as vegetables being prepared for freezing)
   2. to scald (almonds) so as to remove the skins
5. Metallurgy to brighten with acid or by coating with tin

Etymology: ME blanchen < OFr blanchir < blanc, white: see blank

intransitive verb