Definition of collapsing:
(v) :
(intransitive) To break apart and fall down suddenly; to cave in.
(v) :
(intransitive) To cease to function due to a sudden breakdown; to fail suddenly and completely.
(v) :
(transitive) To cause something to collapse.
(v) :
(intransitive) To pass out and fall to the floor or ground, as from exhaustion or other illness; to faint.
(v) :
(intransitive) To fold compactly.
(v) :
(transitive, computing) In a hierarchical list (such as a directory tree or table of contents), to hide the subentries of (an entry).