piano chord
E♭maj9
E♭1G3B♭5D7F9
A major seventh with a ninth on top.
Written the other way round it is D♯maj9 — the same twelve keys on a piano, a different piece of notation.
What is true of it
E♭maj9 is E♭, G, B♭, D and F — 1, 3, 5, 7 and 9 counted from E♭.
On an instrument that cannot reach all 5, the 5 and 1 go first, in that order.