son·ic 
(sŏnĭk)
(sŏnĭk)adj.
1. Of or relating to audible sound: a sonic wave.
2. Having a speed approaching or being that of sound in air, about 1,220 kilometers (760 miles) per hour at sea level.
3. Slang Extremely exciting and fast-paced: a sonic lifestyle.
[From Latin sonus, a sound; see swen- in the Appendix of Indo-European roots.]
sonic·al·ly adv.