0 used to describe something on a coat of arms (= a special shield or shield-shaped pattern that is the sign of a family, university, or city) that is red:
He came across a group of German knights, one of whom wore a coat of arms (argent two bars gules) identical to his own.
The crest should rest on a torse, which is a twisted cord divided vertically into six sections, colored alternately argent and gules.
