Available Definitions:
1) a. - Being in a state of repose; at rest; still; not moving; as, a quiescent body or fluid.
2) a. - Not ruffed with passion; unagitated; not in action; not excited; quiet; dormant; resting.
3) a. - Not sounded; silent; as, y is quiescent in "day" and "say."
4) n. - A silent letter.