| Term No. | Term Name | Term Description |
| 4698 | V-drag, or V-crowder | A V-shaped wooden or steel implement for construction and maintenance of small ditches. In operation, the operator stands on the runner board parallel..... |
| 1913 | Vacuole | A cavity in the protoplasm of cells which contains a watery liquid, the cell-sap...... |
| 5648 | Vacuum concrete | A concrete produced by applying a vacuum to the poured concrete by means of the forms or a separate mat, so that the pressure of the atmosphere expels..... |
| 5941 | Vacuum liner | A special form liner made of two layers of screen or wire mesh covered by a layer of cloth. The liner is sealed with rubber or caulking material aroun..... |
| 4502 | Vacuum pump | 1 - A pump for creating a partial vacuum in a closed space. 2 - A pump where water is forced up a pipe by the difference in pressure between the atmos..... |
| 8714 | Vacuum tank | Closed unit where the pressures can be maintained to any desired degree of vacuum so that cavitation effects can be observed readily in a model...... |
| 991 | Vadose water, Gravity suspended water, or Gravitational water | 1 - Water in excess of adsorption water and pellicular water seeping towards water table. 2 - See 1858...... |
| 2321 | Valley | 1 - An elongated depression usually with an outlet between bluffs or between ranges of hills or mountains. 2 - See 2320...... |
| 2463 | Valley floor | Bottom of the canyon or valley...... |
| 1057 | Valley spring | Groundwater discharge to the earth`s surface caused by a sudden change of slope on the side of an erosion valley (See 1054)...... |
| 7968 | Valley storage | 1 - The volume below the water surface profile. 2 - The natural storage capacity or volume occupied by a stream in flood after it has overflowed its b..... |
| 919 | Valley storage, Lateral storage | The natural storage capacity or volume occupied by a stream in flood after it has overflowed its banks. It includes the quantity of water within the m..... |
| 1379 | Valley trenching | Gully erosion occurring in floodplains...... |
| 4790 | Valve body | Main part of a valve through which water flows, and that contains the moving parts and which allows connection to the irrigation system...... |
| 2725 | Valve chamber, or Valve house | A structure housing the regulating valves, control mechanisms for operation of valves and equipment required to remove parts for repair, etc...... |
| 6218 | Valve control point | An electrical panel designed for only one directional valve. One side of it is connected to the directional valve, and the other to the field control ..... |
| 4799 | Valve pressure test | A test that enables to determine the pressure resistance of a complete valve...... |
| 1848 | Vapour movement | Movement of moisture in the vapour stage...... |
| 886 | Vapour pressure | The partial pressure of water vapour in the air or atmosphere...... |
| 4946 | Vapour pressure | Pressure exerted by water vapour contained in the air...... |
| 8579 | Variable | A quantity that can change in a system...... |
| 2354 | Variable radius arch dam, or Variable centre dam | A type of an arch dam when neither the radius nor the central angle is constant. This dam is a compromise between the constant radius and the constant..... |
| 5771 | Varnish | A liquid coating material consisting essentially of a homogeneous mixture of resin, drying oil, drier and solvent and containing no pigment, that flow..... |
| 5754 | Varnish paint | Varnish, usually coloured and often opaque. (See Varnish)..... |
| 795 | Vectopluviometer | A device for separating and measuring the rainfall according to the variation in wind direction during a storm. It consists of a rain gauge with a swi..... |
