Definition of slumps:
(v) :
(intransitive) To collapse heavily or helplessly.
(v) :
(intransitive) To decline or fall off in activity or performance.
(v) :
(intransitive) To slouch or droop.
(v) :
(transitive) To lump; to throw together messily.
(v) :
To fall or sink suddenly through or in, when walking on a surface, as on thawing snow or ice, a bog, etc.
(v) :
(transitive, slang) To cause to collapse; to hit hard; to render unconscious; to kill.