Red Baron

bleed red ink

To suffer from severe net losses.

clap one's hands red

To clap or applaud intensely.

cut red tape

To reduce bureaucracy.

neither fish, flesh, nor good red herring

Synonym of neither fish nor fowl (“not easily categorized; not rightly belonging or fitting well in a given group or situation; also, not having the advantages of the various options”).

paint the town red

To party or celebrate in a rowdy, wild manner, especially in a public place.

put on the red light

To advertise oneself as a prostitute.

red face test

A hypothetical test of a person's embarrassment that is either passed or failed. Saying one passes the red face test means one would not blush and thus would not be embarrassed by disclosing something to others or doing something, and saying one fails the red face test means a situation would cause them discernible embarrassment.

red flag

Something that will enrage a particular person; a red rag.