*washout*

n. 1. The washing out or away of earth, etc., especially of a portion of the bed of a road or railroad by a fall of rain or a freshet; also, a place, especially in the bed of a road or railroad, where the earth has been washed away. [ 1913 Webster ]

2. a complete failure; -- of an enterprise. [ PJC ]

3. a person who has failed a course of study or training, leaving the program before its completion. [ PJC ]