C m11/F
The C m11 chord consists of the C (Perfect unison), Eb (Minor third), G (Perfect fifth), Bb (Minor seventh), D (Major ninth) and F (Perfect eleventh) notes, with F as the bass note.

How to play the C m11/F chord
- Play F as the lowest bass note in the left hand
- Find C (Root) on the piano keyboard
- Add Eb (Minor third) — 3 semitones above C
- Add G (Perfect fifth) — 7 semitones above C
- Add Bb (Minor seventh) — 10 semitones above C
- Add D (Major ninth) — 14 semitones above C
- Add F (Perfect eleventh) — 17 semitones above C
- Press all 7 notes simultaneously to sound the C m11/F chord