/ Dictionary / Index E extrachromosomal: Meaning and Definition of Find definitions for: ex•tra•chro•mo•so•mal Pronunciation: (ek"stru-krō"mu-sō'mul), [key] — adj. Genetics. of or pertaining to DNA that exists outside the main chromosome and acts independently. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. extracellular extra-condensed Related Content Daily Word Quiz: blanch Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language