micronucleus

noun, plural mi·cro·nu·cle·i [mahy-kroh-noo-klee-ahy, –nyoo-] /ˌmaɪ kroʊˈnu kliˌaɪ, -ˈnyu-/. Biology.

1. the smaller of the two types of nuclei occurring in ciliate protozoans.

noun plural -clei (-klɪˌaɪ) or -cleuses

1. the smaller of two nuclei in ciliated protozoans, involved in reproductionCompare macronucleus

n.

1. A minute nucleus.
2. The smaller of two nuclei in ciliate protozoans that contains genetic material and functions in reproduction.