siditty etymology? BE for feeling superior(1967)

[Sam Clements]

I have nothig to add as far as the etymology.  DARE  and OED cite from Jet in 1967....."Eartha..is considered 'seditty' by many Negroes."

The DARE entry also lists the spellings as "saddity, sadiddy, saditty, seditty, siddity."  Etymology unknown. 

I'm just wondering if Wilson has anything to contribute, given his age and experience.  Especially since one of the early cites is Angelou(1968-70).  

"St. Louis teachers, on the other hand, tended to act very siditty, and talked down to their students from the lofty heights of education whitefolks' enunciation."  

She also had other useages from that date.  She later, in the same source, spelled it 'siddity.'

If I missed a previous discussion from the archive, I'm sorry.

Sam Clements