v. 1 fall (down or in or apart), crumple, cave in, deflate, crumble, tumble down, break down, go When he opened the valve, the balloon collapsed Hundreds of buildings collapsed in the earthquake. 2 fail, (come to an) end, fall through, peter out, disintegrate, dissolve, fall flat, founder, come to naught or nought, break up or down; decline, diminish; disappear, evaporate, go up in smoke, go bankrupt, go under, Brit go to the wall, Colloq fizzle out After the imprisonment of their leader, the entire movement collapsed Owing to the recession, many businesses collapsed. 3 pass out, faint, drop, Colloq keel over; Old-fashioned or literary swoon He collapsed on-stage and they took him to his dressing-room 4 break down (mentally), have a (nervous) breakdown, go to pieces, come or fall apart , Colloq crack up, US also crack She finally collapsed from overwork and is now in a sanatorium
n. 5 cave-in, breakdown The collapse of the house was attributed to termites 6 failure, downfall, ruin; disappearance, disintegration, dissolution, bankruptcy Will he be able to survive the collapse of his financial empire? 7 (mental) breakdown, prostration, Colloq crack-up: He suffered a mental collapse when his family was killed in a car crash