/ Dictionary / Index D dilation: Meaning and Definition of Find definitions for: di•la•tion Pronunciation: (dī-lā'shun, di-), [key] — n. the act of dilating; state of being dilated. dilatation. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: dilation (Thesaurus) dilate dilative Related Content Daily Word Quiz: diligent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language