Flossie was early 20th century slang for a disreputable woman or promiscuous girl, or a prostitute. It may have originated as a variation of flossy meaning "fancy, frilly" (1890s slang). ‘Floy floy’ was American slang for venereal disease. The song ‘Flat foot floozie (with the floy floy) ‘was written by Bulee "Slim" Gaillard, Slam Stewart and Bud Green. It was performed in 1938 by Slim Gaillard and became a major hit. Slim was a polyglot, rather eccentric and spoke “Vout” language. He was also fluent in gibberish and double-talk. Gaillard sang in vocalese which is unlike scat singing, i.e. improvised nonsense syllables. Vocalese uses lyrics, either improvised or set to pre-existing instrumental solos. The inventor and most prolific practitioner of vocalese was Eddie Jefferson, whose rendition of Coleman Hawkins's "Body and Soul" became a hit on its own. Annie Ross recorded “Twisted" (1952), which is now considered a classic of the genre.
In his unique style Slim Gaillard combined vocalese improvisations with scat singing. This hip style had broad appeal to the merging jazz generation. Despite his obvious eccentricities he was very well respected by his peers. ‘Flat floozie (with the floy floy) ‘was recorded by many jazz and pop luminaries including: Louis Armstrong and The Mills Brothers (1938); Benny Goodman. Wingy Manone, Django Reinhardt, Count Basie, Fats Waller, and Michael Jackson. The original title had to be changed from "Flat foot floozie, (with the 'floy-floy)” into 'Flat foot floogie with the floy floy' to avoid censorship and allow airplay. A “Floogie” dance craze followed the success of the record and together the song and dance craze proved so popular and representative of American culture at the time, the sheet music was placed in a time capsule at the 1939 World’s Fair, not to be opened for 5,000 years. Many early jazz and rock’n roll hits contained lyrics which had previously been considered to vulgar for a white public consumption and all expletives and reference to sex and the seamier side of life were removed or vocalesed.
In his private life Gaillard like other musicians did in the normal course of events become exposed to the daily lives of sex workers and ordinary people coping with untreated sexually transmitted disease. Sadly their prognosis was poor and the symptoms of end stage syphilis, horrific. Tabes dorsalis occurs with untreated syphilis infection and is a slow degeneration of the sensory neurons in the spinal cord. These are responsible for proprioception, vibration, and discriminative touch. Most street walkers inevitably fell prey to syphilis tabes dorsalis only appearing many decades later. Symptoms included painful legs and paresthesias with formication and hypoesthesias. Locomotor ataxia with tabetic gait followed. Due the loss of propriception victims walked with a high stepping gaiting slapping their feet noisily on the floor. The flat footed sex-worker with venereal disease in the song accurately described tertiary syphilis. It was also a common misconception at the time, Tabes dorsalis was caused by sexual excess and anyone considered promiscuous was thought would end up flat footed. So the lyrics of the popular song were a warning to the unsuspected. Sadly the incidence of STDs today is increasing due to unprotected sex.