In music theory, a diminished third is an interval that has two half steps 
The diminished third requires that:
- The interval must be a third interval (three note names between the first and the last).
- The interval must have two half steps.
What does a diminished third look like?
Here is an example of a melodic diminished third (two music notes in a melody) and a harmonic diminished third (in a chord):
How to recognize a diminished third?
Rule of music theory: All intervals in a major scale starting with the tonic (degree I) are either major or perfect, and only unison, octave, fourth and fifth are perfect (the others are major).
Example with the interval C / E♭♭:
Let's take the to have C as the tonic:
From the rule stated above, the interval C / E♮ is a major third, so the interval C / E♭ is a minor third, and so the interval C / E♭ is a diminished third.
Inversion of the diminished third
The inversion of the diminished third is the augmented sixth.
Here is an example of a augmented sixth:
Musical examples of diminished third
No examples yet, but feel free to send me some examples!
Interval identification game
You will find this interval in my Intervals identification game:
