Long, well-cut, slicked back hair often seen on the heads of those in various money managing fields. This hair style is very often used in the movie business when depicting a banker.
"Banker" derives from the term used to describe the profession of all persons in the money management field, "Flow" deriving from the term for hair most commonly associated with hockey players.
#1: "You're hair is getting pretty long there."
#2: "I know. Almost Banker Flow status."
Matt Bomer (in White Collar), Jon Hamm (in Mad Men), Michael Douglas (in Wall Street (1987)), and just about every character in 'Margin Call'.