We don't have synonyms for idioplasma yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are idioplasm and idioplasmic.
(n) :
(biology, archaic) A 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.
(n) :
(biology, archaic) A 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.