Source : Webster's Revised Unabridged Dictionary (1913)

Mycoderma \My`co*der"ma\, n. [NL., from Gr. my`khs a fungus +
   de`rma skin.]
   1. (Biol.) One of the forms in which bacteria group
      themselves; a more or less thick layer of motionless but
      living bacteria, formed by the bacteria uniting on the
      surface of the fluid in which they are developed. This
      production differs from the zo["o]l[oe]a stage of bacteria
      by not having the intermediary mucous substance.

   2. A genus of micro["o]rganisms of which the acetic ferment
      ({Mycoderma aceti}), which converts alcoholic fluids into
      vinegar, is a representative. Cf. {Mother}.