The Collaborative International Dictionary of English v.0.48:
Nucleoplasm \Nu"cle*o*plasm\, n. [Nucleus + -plasm.] (Biol.) The matter composing the nucleus of a cell; the protoplasm of the nucleus; karyoplasma. [1913 Webster]WordNet (r) 3.0 (2006):
nucleoplasm n 1: the protoplasm that constitutes the nucleus of a cell [syn: nucleoplasm, karyoplasm]