game face
n.— «He slumped in his chair, rested his head on the palm of his extended arm, and glared at the 20 or so mostly black male job seekers who gathered on a recent Monday, the first day of a four-week job-readiness training program.…The men were talking about “game face,” slang for the menacing expression worn by many African-American and Hispanic men who live in inner cities. But many men who wear their game faces on the streets also wear them on interviews and at work.» —“Sometimes the Right Approach Is Putting the Best Face Forward” by Tanya Mohn New York Times May 7, 2005. (source: Double-Tongued Dictionary)
Further reading
It’s hard to imagine now, but there was a time when people disagreed over the best word to use when answering the phone. Alexander Graham Bell suggested answering with ahoy! but Thomas Edison was partial to hello! A fascinating new book about...