For the cosmetic, see Rouge (cosmetics). To blush is to display redness in one's face; the term is seldom applied except when the redness is construed as a result of embarrassment, shame, or modesty. Blushing is generally distinguished, despite a close physiological relation, from flushing, which is more intensive and extends over more of the body, and seldom has a mental source.
See more at Wikipedia.org...