red inknoun [ U ]
ukusinformala situation in which a company is losing a lot of money:
The line between profitability and red ink in a bookstore is so thin that even the little decisions are important.
bleed/leak/spill red ink The parent company has been falling apart for several months, bleeding red ink, and losing clients.
the flow/tide/sea of red ink The boom a decade ago has now given way to a sea of red ink.