To fall together suddenly, as the sides of a hollow vessel; to close by falling or shrinking together; to have the sides or parts of (a thing) fall in together, or be crushed in together; as, a flue in the boiler of a steam engine sometimes collapses.
- To fall down or inward suddenly; cave in.
- To break down suddenly in strength or health and thereby cease to function: a monarchy that collapsed.
- To fold compactly: chairs that collapse for storage.
- To cause to fold, break down, or fall down or inward.
- The act of falling down or inward, as from loss of supports.
- An abrupt failure of function, strength, or health; a breakdown.
- An abrupt loss of perceived value or of effect: the collapse of popular respect for the integrity of world leaders.