Pronunciation: (dī-as'tl-ē", -tl-ē), [key]
1. Physiol.the normal rhythmical dilatation of the heart during which the chambers are filling with blood. Cf. systole (def. 1).
2. Pros.the lengthening of a syllable regularly short, esp. before a pause or at the ictus.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.