As a music theory coach I sometimes get rather weird questions — this is one of them: What is the longest musical chord name you could construct?

In fact you could construct pretty long chord names. Let me give it a shot:

Bb7#9b9#11#5/Ab

Now I don’t know if this chord would sound great — it’s just an altered Bb dominant chord over Ab. The maximum number of options is limited by the notes we have: we have 7 notes in the scale, of which 2–3 (root, third and the implicit fifth) are already encoded in the basic chord name; this leaves 4–5 options: 5,7,9,11 and 13. With some options it makes sense to alter them high and low, as I did with the 9 above.

You can spell out every single option to use in a chord like this, but normally you wouldn’t do it. Just writing

Bb7#9

would have most musicians play the same chord. The shorter symbol is enough to state that this should be an “altered dominant” chord. It is up to the instrumentalist to add matching alterations as they see fit — the #9 merely stands as a placeholder for alterations like b9, #5, b13, #11 and the like.

The goal with chord symbols is NOT to spell out every note to play (staff notation is much better suited for this), but to be quickly recognizable while playing. Chord symbols are more in the history of figured bass, where performers were expected to come up with matching notes and chords, than in the history of romantic music, where composers tried to write out every minute detail of the sound (sometimes ending in horribly complex looking staff notation).

Figured bass is most similar to our chord notation today
Romantic music trying to notate as much performance detail as possible

But if your goal, just for the sake of it, is to really produce long chord symbols, you could walk into the realm of polychords (i.e. playing one chord over another). This allows you to essentially double the length of your chord symbol:

Bb7#9b9#11#5/Abmaj7#9b9#11#5

Again, this would be defeating the purpose of chord symbols as quickly scannable and recognizable playing advices. But for sake of making it long, it would certainly work 😁.