Thanks Mac! So here's my edited note:

diminished chord (triad) is 1 b3 b5 (Cdim or Cm-5 or Cmb5 but Cdim often implies Cdim7)
diminished seventh is 1 b3 b5 7bb (Cdim7)
half-diminished is 1 b3 b5 b7 (minor seventh) (Cm7b5)

is that right?