The Collaborative International Dictionary of English v.0.48:
Turbulency \Tur"bu*len*cy\, n. Turbulence. [1913 Webster] What a tale of terror now its turbulency tells! --Poe. [1913 Webster]WordNet (r) 3.0 (2006):
turbulency n 1: unstable flow of a liquid or gas [syn: turbulence, turbulency]