the erosive process of washing away soil or gravel by water (as from a roadway); "from the house they watched the washout of their newly seeded lawn by the water"
the channel or break produced by erosion of relatively soft soil by water; "it was several days after the storm before they could repair the washout and open the road"
throw into great confusion or disorder; "Fundamental Islamicists threaten to perturb the social order in Algeria and Egypt"
disturb in mind or make uneasy or cause to be worried or alarmed; "She was rather perturbed by the news that her father was seriously ill"
cause a celestial body to deviate from a theoretically regular orbital motion, especially as a result of interposed or extraordinary gravitational pull; "The orbits of these stars were perturbed by the passings of a comet"
disturb or interfere with the usual path of an electron or atom; "The electrons were perturbed by the passing ion"