Terms and symbols in chord names
Add (as in add9): The 9th is added to the triad (7th is not present)
Notation Example: Dadd9
Alt (altered)–means that 5th, 9th, and 13th are ALL either flatted or sharped (player’s discretion as to which to include in a chord voicing).
Notation Example: C7(alt)
Augmented: The 5th is sharped
Notation Examples: C+, Caug, C7+, C7(+5)
Diminished: Both the 3rd and 5th are flatted.
Notation examples: Cdim, C°, C°7
Dominant: Contains a flatted 7th, as well as a natural 3rd & 5th.
Notation examples: C7, C9, C11, C13 (all of these are “dominant” chords)
Flat: Lowered by 1/2 step. Symbol looks like a lower-case b (very difficult to get this symbol to work well on web pages, so I just use the lowercase b)
Notation example: Bb, Ebm7
Half-Diminished: A.K.A. “minor 7 flat 5”, a chord containing a minor 3rd, a flat 5th, and a flat 7 (note that a full diminished chord contains a double-flat 7th).
Notation Examples: Cm7b5, Cm7(b5), CØ
Major: Contains natural (a.k.a. “major”) 3rd and natural 5th.
Notation examples: Cmaj7, CΔ
Minor: Contains a flat (a.k.a. “minor”) 3rd and a natural 5th.
Notation examples: Cm, Cm7, C-, C-7
Sharp: Raised by 1/2 step.
Notation examples: C#, C#m, C#dim, etc.
Sus (suspended): 3rd is omitted (suspended), usually replaced with 2nd or 4th.
Notation examples: Csus, C7sus, Csus2, Csus4