The Collaborative International Dictionary of English v.0.48:

Hemi-demi-semiquaver \Hem`i-dem`i-sem"i*quaver\, n. [Hemi- +
   demi-semiquaver.] (Mus.)
   A short note, equal to one fourth of a semiquaver, or the
   sixty-fourth part of a whole note.
   [1913 Webster]