Webster's Revised Unabridged Dictionary · 1913

Idioplasma

Idioplasma , noun

[New Latin, from Greek 'i`dios proper, peculiar + {not transcribed} a form, mold.]

(Biology) That portion of the cell protoplasm which is the seat of all active changes, and which carries on the function of hereditary transmission; -- distinguished from the other portion, which is termed nutritive plasma. See Hygroplasm.