To fall together, or into an irregular mass or flattened form, through loss of firm connection or rigidity and support of the parts or loss of the contents, as a building through the falling in of its sides, or an inflated bladder from escape of the air contained in it.Figuratively— To break down; go to pieces; come to nothing; fail; become ruined: as, the project collapsed.In pathology, to sink into extreme weakness or physical depression in the course of a disease.To appear as if collapsing; lose strength, courage, etc.; subside; cease to assert one's self or push one's self forward: as, after that rebuke he collapsed.n. A falling in or together, as of the sides of a hollow vessel.n. Figuratively, a sudden and complete failure of any kind; a breakdown.n. In medicine, an extreme sinking or depression; a more or less sudden failure of the vital powers: as, the stage of collapse in cholera.