ˌmaritoˈnucleusBiol.rare. [f.marito-, used as comb. f. of L. marītus married + nucleus.] (See quot.) 1884Hyatt in Proc. Boston Soc.Nat.Hist. XXIII. 54 Reserving..the name of maritonucleus or married nucleus for the renovated nucleus of the egg after its union with the male pronucleus.