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

The transverse section of a cyclonic area where the barometric pressure, neither rising nor falling, has reached its lowest point.

The bottom between two waves.

The trough line of a circular depression is the line, through the centre, perpendicular to the line of advance of the centre. During the passage of a depression over any given place the pressure at first falls and later rises; the trough line passes over the place during the period of transition from the falling to the rising barometer. The word trough is also used in a more general sense for any 'valley' of low pressure, and is thus the opposite of a 'ridge' of high pressure.

A region of cyclonic (counter-clockwise) curvature of winds in the atmosphere, located around a low-pressure area. Troughs are generally associated with cloudy, cool, unsettled, and wet weather.

Often recognized as a "Trough of Low Pressure". A Trough is an area of generally low atmospheric pressure. Troughs occur at all levels of the atmosphere. Upper level troughs drive airmasses toward the southeast usually causing stormy weather. Surface troughs often precede cold fronts causing a lowering of pressure and a wind shift.

charting term, also known as a bottom (eg. in charting prices, a trough is the point where the price bottoms before the pressure to buy pushes it back up). (See also Peak).

A trough of low pressure is indicated by isobars extending outwards from an area of low pressure. It has associated with a trough line which often indicated on a synoptic chart. The pressure at a point on a trough is lower than that at an adjacent point on either side of the line.

The point in the business cycle when an economic contraction reaches its lowest point before turning up. Contrasts with peak.

A point in the business cycle corresponding to the end of the slowdown and the beginning of expansion.

The lower turning point of a business cycle; the point at which the economy turns from contraction to expansion. Back to the top

A low point in the business cycle, and also a turning point. After a trough, the economy begins to expand. (See also Business cycle.) View LEI Lesson(s) that address this term

High-temperature (180+) concentrator with one axis-tracking.

A colloquial and descriptive name of the parabolic cylinder (surface of constant parabolic cross-section) used for collecting solar radiation along the focal length. Trough systems follow the path of the sun by pivoting on one axis (typically East-West or North-South), using shiny parabolic troughs to heat the collector fluid that passes through a tube at the focus. Below is an illustration from the Solar Radiation Data Manual for Flat Plate and Concentrating Collectors.

a solar tracking mirror, either one or two axes, that generally reflects sunlight onto a linear receiver that is perpendicular to and is in alignment with the sun and the central axis of the linear parabolic mirror

The minimum drug concentration in the blood, usually just before the next dose.

a long, shallow container that holds animal food or water OR a shallow ditch where manure goes before it is taken away.

a long narrow shallow receptacle

1. A drainage ditch. 2. A framing member installed above and perpendicular to the ceiling joists.

ruts, or the deep path through the moguls

A deep path, full of ruts, between moguls.

Deep path of ruts that runs between moguls.