Believe it or not (believe it!), Sexmoan was a name of a town in Pampanga in Central Luzon, Philippines.
The town’s original name, Sasmuan, was apparently corrupted into “sexmoan” by American servicemen from Clark Air Field who were all over Angeles City and nearby towns when Clark Air Field was still a US Military Base.
The town’s name has since been restored to Sasmuan, although some people and even printed materials still refer to it as “Sexmoan.”
According to Wikipedia.org, “Sasmuan” was derived from the Malayo-Polynesian word “pitagmuan” or “meeting place of the datus.”