Main Entry: nu·cle·ate Pronunciation: 'n(y)ü-klE-"At Function: verb Inflected Forms: -at·ed; -at·ing transitivesenses 1: to form into a nucleus 2: to act as a nucleus for 3: to supply nuclei to nucleateintransitive senses 1: to form a nucleus 2: to act as a nucleus 3: to begin to form