# What is this 'degree' symbol on a roman numeral chord?

I found this neat tool online to save me having to draw out a circle of fifths myself, and clicking on the key you are writing in even shows you the chord 'family'. Since I'm writing in F minor I clicked on that but I'm unfamiliar with the small degree-like symbol that came up next to the ii on Gm. What does it mean? Thanks in advance.

The little circle means "diminished" - so this is a diminished chord(See: https://en.m.wikipedia.org/wiki/Chord_notation)

A diminished chord is a triad with two minor thirds above the root - or you can think of it as a minor chord with a flatted fifth.

• It's a little confusing because it's next to Gm, which is G-Bb-D. The ii dim would be G-Bb-Db. May 14, 2023 at 21:02
• That particular tool is inaccurate. It labels Gm as Go, which is a different chord. There are better examples to be found.
– Tim
May 15, 2023 at 7:36
• @Tim how do these better examples work? With another ring of diminished chords inside the one with the minor chords? Given the relationship between the two rings shown here, of relative major to relative minor, it seems you'd still have some sort of confusion. There's no such thing as "relative diminished," after all. May 20, 2023 at 9:36

It is the symbol for a diminished chord. The ii chord in F minor is G-Bb-Db, a triad with a minor third and a diminished 5th. That is the construction for any diminished triad but it is diatonic to the key of F minor. It is also diatonic to its relative major, Ab, in which case it would be a viio.

The "degree" symbol means a diminished chord. Thus, ii° is a diminished chord built on scale degree 2. In the key of F minor, it's G diminished (G-Bb-Db).

Adding a little wider information to the fact that 'o' means a diminished chord - built on the 2nd degree of the minor scale (and 7th degree of the major). Because of the way the notes fall, there will be a m3 and a diminished 5 - hence the name.

In any given key, there will be seven different chords produced from the seven different notes. Each chord having its root on one note from the scale, and two thirds 'piled' on top of that. All notes being diatonic - from the key/scale.

So, that will produce three major triads - I, IV and V, and three minors ii, iii and vi. In key C, it's C Dm, Em, F, G, Am, and the one in question B °.

• Note that there are three forms of the minor scale, and OP's tool is showing the form with both 6th and 7th notes of the scale flattened. When the 7th is raised (E flat to E natural as in the harmonic minor) some of the chords change, for example III changes from major to augmented (A-flat, C, E). II remains diminished though. May 14, 2023 at 13:47