trough

n. long and narrow receptacle (e.g. for holding food and water for animals); channel or drain for transporting water; elongated depression between two waves; elongated area of low pressure (Meteorology); low point

A trough is a long box-like drinking vessel for farm animals. In other fields, "trough" refers to any kind of (usually elongated) depression:In physics, a trough is the lowest point on a wave.In meteorology, a trough is an elongated region of low atmospheric pressure.In geology, a trough is a long depression less steep than a trench.In statistics and economics, a trough is a noticeable and statistically recordable decline in an economy or graph.In chemistry, a Langmuir-Blodgett trough is a laboratory instrument.
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Noun
1. a narrow depression (as in the earth or between ocean waves or in the ocean bed)
(hypernym) natural depression, depression
2. a channel along the eaves or on the roof; collects and carries away rainwater
(synonym) gutter
(hypernym) channel
(hyponym) chute, slide, slideway, sloping trough
(part-holonym) gable roof, saddle roof, saddleback, saddleback roof
3. a concave shape with an open top
(synonym) bowl
(hypernym) concave shape, concavity, incurvation, incurvature
4. a treasury for government funds
(synonym) public treasury, till
(hypernym) treasury, exchequer
5. a long narrow shallow receptacle
(hypernym) receptacle
(hyponym) rocker, cradle
6. a container (usually in a barn or stable) from which cattle or horses feed
(synonym) manger
(hypernym) container
(hyponym) bunk, feed bunk

(n.)
Any channel, receptacle, or depression, of a long and narrow shape; as, trough between two ridges, etc.
  

(n.)
A long, hollow vessel, generally for holding water or other liquid, especially one formed by excavating a log longitudinally on one side; a long tray; also, a wooden channel for conveying water, as to a mill wheel.
  

The transition point between economic recession and recovery.