Bravo Zulu
It stems from flag codes and is an administrative signal for "well done".
Ever since, Bravo Zulu has become Navy jargon for "Well Done" or "Outstanding."
Speaking of - if you want an example of Follow the Wives - Operation Creek, conducted by the British, was entirely clandestine. The men involved could receive zero recognition they were ever part of the war. However, what they did come up with to signify their involvement was a broche given to their wives - a seahorse - which they would wear at their husbands' request at social gatherings and the like.