International Commission on Irrigation & Drainage Commission Interationale des Irrigation et du Drainage
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...... |
58 | Variable | Generally, any quantity that varies. More precisely, a variable is a quantity that may take any one of a specified set of values. The variable may be ..... |
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..... |
116 | Variance | A measure of the degree of dispersion of a set of values around their mean, obtained by calculating the mean value of the squares of the deviations fr..... |
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..... |
The Multilingual Technical Dictionary (MTD) is an e-dictionary of all technical terms related to irrigation, drainage, flood management, environment, river training, and allied disciplines of the water sector. Any term/ definition can be printed/copied with the option to download/updates of terms from the ICID website. The MTD enriches the process of sharing and exchange of experiences and has proven to be highly useful for engineers, researchers, students, professionals, planners, designers, academics and all others related to the field of irrigation and drainage. It is more helpful for professionals outside the water sector, in simplifying the technical jargon and to understand the sectoral nuances easily.
As part of ICID's flagship activity, it was first published in English and French languages in 1967, the – 4th edition of the MTD (English-French) was brought out on CD-ROM in the year 2002. Currently, we are following the 5th edition released in 2009, which defines 9,370 technical terms in Chinese, Japanese and Russian, besides English and French. This online version of MTD is based on the 5th edition's DVD format. This version includes 9370 technical terms with matching English and French translation. The DVD version also includes terms collected in Chinese, Japanese and Russian languages with the active support received from respective National Committees. However, full integration with online versions has not taken place due to the difference in available translation editions/ versions. National Committees of Iran, China, Japan, Russia, Korea, and India are working on the translation/ updating part to match the present online version.