piano chord
D♯dim7
D♯1F♯♭3A♭5C♭♭7
Three minor thirds stacked. The seventh is doubly diminished, which is why it is written with a double flat.
Written the other way round it is E♭dim7 — the same twelve keys on a piano, a different piece of notation.
What is true of it
D♯dim7 is D♯, F♯, A and C — 1, b3, b5 and bb7 counted from D♯.