1. 1. Pulsing or throbbing with energy or activity: the vibrant streets of a big city.
   2. Vigorous, lively, and vital: "a vibrant group that challenged the . . . system" (Philip Taubman).
2. Exhibiting or characterized by rapid, rhythmic movement back and forth or to and fro; vibrating.
3. Produced as a result of vibration; resonant or resounding: vibrant voices.
4. Relatively high on the scale of brightness: a vibrant hue.

The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.