C# Minor 9b5, 4th inversion (D# in the bass)
Also written as C#m9b5/D#.
Notes, from the bass up
D# (bass)C#EGB
The same notes as C# Minor 9b5 (D#, C#, E, G and B), rearranged so D# is the lowest note. Use it to move between chords with smaller jumps across the keyboard.