From Longman Dictionary of Contemporary Englishwashoutwash‧out /ˈwɒʃ-aʊt $ ˈwɒːʃ-, ˈwɑːʃ-/ noun [countable] informal 1 FAILa failure The picnic was a total washout – nobody turned up!2 DNSGan occasion when heavy rain causes damage or stops an event from happening → wash out at wash1
Examples from the Corpus
washout• Parts of Highway 40 remain closed due to mudslides and washouts. 