One of the mysteries of the English language finally explained.
The action of signalling with, flying, or marking something with a red flag; specifically the action of identifying someone or something as a cause for concern or as warranting special attention.
Late 19th century; earliest use found in Boston Advertiser. Originally from red flag + -ing. In later use also partly from red-flag + -ing.
In this article we explore how to impress employers with a spot-on CV.