COTD 12: B-Δ11

I don't know what this chord should be named. I generally think of chords as falling into four types based on their guide tones, the third and the seventh:

Major: a major third and major seventh
Minor: a minor third and minor seventh
Dominant: a major third and minor seventh
Minor Major: a minor third and major seventh (I know, that's a terrible name for it)

The only chords that get just a plain number are the ones that follow the dominant path, e.g. C9, a dominant chord, a major third (E) and minor seventh (B♭). The other three paths all need a modifier before their number to say what they are. In this case, I present a dreaded "Minor Major" chord, but I'll abbreviate "Minor Major" as -Δ.

B-Δ11
X2233X

I guess it's just a C9 with a flatted root. It's evocative of the last chord of the song New Machine by Chris Whitley.

Now that I mention it:

My Favorite Chris Whitley Albums in Rough Order
1) Dirt Floor
2) Living With the Law
3) Perfect Day
4) Din of Ecstasy (which has New Machine)

Other essential songs include Silhouette from Hotel Vast Horizon and his cover of When I Paint My Masterpiece from Dislocation Blues, released posthumously.