[red] Red is a primary color and the color of blood. As you might expect, it has many uses in language.
in the red
losing more money than you earn. ‘Because of all of our unforeseen expenses this month, we’re going to be in the red.’
information that is used to mislead someone. ‘The test had a few obvious red herrings, so I knew to choose the opposite.’
angry. ‘I was seeing red when I found my wife with another man. Fortunately, it was her brother.’