piano chord
A♭m9
A♭1C♭♭3E♭5G♭♭7B♭9
A minor seventh with a ninth on top.
Written the other way round it is G♯m9 — the same twelve keys on a piano, a different piece of notation.
What is true of it
A♭m9 is A♭, C♭, E♭, G♭ and B♭ — 1, b3, 5, b7 and 9 counted from A♭.
On an instrument that cannot reach all 5, the 5 and 1 go first, in that order.