slump

v. fall, collapse; droop, slouch; decline, decrease, deteriorate; sink down, settle

n. recession, sudden decrease; drooping posture, slouch; collapse; period of time in which performance is poor

Slump is a form of mass wasting event that occurs when loosely consolidated materials or rock layers move a short distance down a slope. When the movement occurs in soil, there is often a distinctive rotational movement to the mass, that cuts vertically through bedding planes (landslides take place along a bedding plane or fault). This results in internal deformation of the moving mass consisting chiefly of overturned folds called "sheath folds." The surface of the mass often remains relatively undisturbed, especially at the top. The area where the mass broke away from the slope is often cliff-like and concave. This area is known as the "scarp."
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Noun
1. a noticeable deterioration in performance or quality; "the team went into a slump"; "a gradual slack in output"; "a drop-off in attendance"; "a falloff in quality"
(synonym) slack, drop-off, falloff, falling off
(hypernym) deterioration, decline in quality, declension, worsening
(derivation) fall off, sink
2. a long-term economic state characterized by unemployment and low prices and low levels of trade and investment
(synonym) depression, economic crisis
(hypernym) financial condition, economic condition
(hyponym) Great Depression
(derivation) fall off, sink
Verb
1. assume a drooping posture or carriage
(synonym) slouch
(hypernym) sag, droop, swag, flag
2. fall or sink heavily; "He slumped onto the couch"; "My spirits sank"
(synonym) slide down, sink
(hypernym) collapse, fall in, cave in, give, give way, break, founder
3. fall heavily or suddenly; decline markedly; "The real estate market fell off"
(synonym) fall off, sink
(hypernym) drop
(verb-group) sink, drop, drop down
(derivation) depression, economic crisis
4. go down in value; "the stock market corrected"; "prices slumped"
(synonym) decline, correct
(hypernym) descend, fall, go down, come down

(v. t.)
To lump; to throw into a mess.
  

(v. i.)
To fall or sink suddenly through or in, when walking on a surface, as on thawing snow or ice, partly frozen ground, a bog, etc., not strong enough to bear the person.
  

(n.)
The noise made by anything falling into a hole, or into a soft, miry place.
  

(n.)
The gross amount; the mass; the lump.
  

(n.)
A boggy place.
  

A temporary fall in performance, often describing consistently falling security prices for several weeks or months.