The definition and origin of the term rugalator seems to remain a mystery to the world outside of New Orleans. Incredibly, the best resource of the etymology of the word is the website, UrbanDictionary.com, which suggests it is a percussive instrument used in a voodoo ceremony, presumably shaken like a maraca. However, the more popular street-definition is that it is slang for, well, the butt. While not surprising at all, it emphasizes the distinct New Orleans vernacular known only to those living within its vibrant culture.
The deep influence of the jazz language is present within Craig Klein's trombone playing, making use of chord substitutions and a softer attack to his tone rather than relying on funkier rhythms of a street parade, but his ideas are traditional enough that can be widely understood. On this tune, a minor blues, the pentatonic melody is repeated with a slight variation, and then uses subtle syncopation before arriving at the "shake your rugalator" phrase. His message is loud and clear, his phrases are a bit more colorful but his point is not lost on a clueless audience.
Like the words of great writers that seem to leap off the page, what separates the artists from the crowd is the way in which they can animate an idea, and Craig Klein's trombonisms take on a life of their own. The first chorus of blues is simple and defines the boundaries of its form. The second chorus elaborates on these ideas, as to be expected in the jazz idiom, with the use of chromaticism through a fountain of notes. However, Klein seems to pull back at the end of these phrases so as to simplify an idea, or to sum it all up. This restraint is what breathes life into his phrasing. And it is the third blues chorus that unveils the local flavor, the laid-back approach to the melody's rhythm that seems to bend time. It is a style of playing that can be felt and understood but not accurately transcribed onto plain paper, perhaps a colorful slang on the classical approach... if you know what I mean.
Here is a YouTube video of Bonerama shaking its collective rugalator.
Recommended reading: 98% Funky Stuff: My Life in Music by Maceo Parker. Published by Chicago Review Press.