Definition of macronucleus
: a relatively large densely staining nucleus of most ciliate protozoans that is derived from micronuclei and controls various nonreproductive functions
Origin of macronucleus
First Known Use: 1892
Medical Definition of macronucleus
plural mac·ro·nu·clei \-ˌī\play also mac·ro·nu·cle·us·es
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