[, ]a situation where sth fails or becomes weaker in a sudden and dramatic way融化（过程）；突然垮掉◆The country is in economic meltdown.这个国家经济崩溃了。◆fears of a meltdown in consumer spending对消费者支出骤减的担忧◆a meltdown on Wall Street (= when the prices of US shares fall suddenly)华尔街股市崩盘