/ Dictionary / Index N nuclear membrane: Meaning and Definition of Find definitions for: nu'clear mem'brane Pronunciation: [key] — Biol. Biol. the double membrane surrounding the nucleus within a cell. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. nuclear medicine nuclear physics Related Content Daily Word Quiz: mamba Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language