/ Dictionary / Index N nucleosynthesis: Meaning and Definition of Find definitions for: nu•cle•o•syn•the•sis Pronunciation: (n"klē-ō-sin'thu-sis, ny"-), [key] — n. Physics, Astron. the formation of new atomic nuclei by nuclear reactions, thought to occur in the interiors of stars and in the early stages of development of the universe. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: nucleosynthesis (Thesaurus) nucleosome nucleotide Related Content Daily Word Quiz: crutiny Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language