Origin of code word
Examples from the Web for codeword
Jazz is now a codeword for sophistication and classiness, even affluence.Jazz (The Music of Coffee and Donuts) Has Respect, But It Needs Love|Ted Gioia|June 15, 2014|DAILY BEAST
A hilton is the codeword for a celebrity, or anyone famous, whether or not they have talent.
Thus "amber" is the codeword for £1; "heliotrope" for £20; "rainbow" for "win and 1, 2."