I came across this while studying harmony and couldn't figure out what its trying to say. It comes from Bach's Partita in A Minor for Flute, BWV 1013, measure 2.
Harmonically, this is a V chord in first inversion, with the chordal 9 added.
Ordinarily, this would be written V9 or, more accurately, Vo7,6, or, even more accurately, V6, because 9 chords really weren't a thing in Bach's time.
This chord symbol seems to be mixing notations by indicating it's a V9 chord and that it contains a diminished interval above the lowest pitch.
Of course, it could just be a mistake in the source.
@aaron is almost there.
It is the bass figure indicating (from the bottom note) fully diminished 7th (°) D (V = fifth note) chord (D°) so inverted with the tonic 9th as the bass note (E).
Typically we now call this #vii° in functional harmony instead of the diminished dominant figuration.
The Bach original inidicates there is no accompaniment, fyi.
Is it wrong: probably as the opening is static a-minor without actually going back and forth V-I, a harmonic feature this figure highlights. The motion is smoother and normally this beat is taken as a substitute-predominant seventh and not part of the cadential dominant, thus extending the cadence length from two beats to two measures.