International Commission on Irrigation & Drainage Commission Interationale des Irrigation et du Drainage
Term No. | Term Name | Term Description |
5702 | Hardness | Resistance to indentation, abrasion, deformation, scratch, etc...... |
1850 | Hardpan, or Ortstein | A formation which occurs by precipitation of dissolved materials, such as calcium carbonate or silica, at certain depths below the surface year after ..... |
8369 | Hardware | The mechanical, magnetic, electrical, and electronic devices or components of a computer...... |
5715 | Hardwood | A conventional term used to denote the wood of broad-leaved trees and it has sometimes no relationship with the physical properties of hardness or str..... |
110 | Harmonic mean | The reciprocal of the arithmetic mean of the reciprocals of each observation...... |
5610 | Harsh mix | A concrete mix that will not compact easily or give a smooth finish...... |
6085 | Haul distance, or Haul | The distance measured along the centre line or most direct practical route between the centre of the mass of excavation and the centre of mass of the ..... |
6083 | Haul road | A road designated for transportation of materials on a project...... |
6087 | Haulageway | A main tunnel connecting underground excavation areas with an exit...... |
8836 | Hazard | The inherent adverse effect that a chemical or other object poses. It is that which has the potential for creating adverse consequences...... |
7115 | Hazard | 1 - A pollutant that may have an adverse effect on man or the environment in a given situation. 2 - The effect of such a pollutant on the environment..... |
7860 | Hazard analysis | Identification, studies and monitoring of any hazard to determine its potential, origin, characteristics and behaviour...... |
7116 | Hazardous substance | A chemical substance or mixture that may have an adverse effect on man or the environment in a given situation. ..... |
7118 | Hazardous waste | A waste material that by its nature is inherently dangerous to handle or dispose of. ..... |
7119 | Hazardous waste management | The systematic control of the collection, source separation, storage, transportation, processing, treatment, recovery, and disposal of hazardous waste..... |
3157 | Hazen-Williams equation | Equation used in the analysis of pressure pipe systems for calculation of velocity of flow or discharge and expressed as- V = k.C.R0.63.S0.54 where,..... |
3678 | Head ditch | The main farm field channel...... |
2964 | Head gate | The control works or the gate itself at the entrance to a conduit...... |
4067 | Head gate | A gate installed at the head of a diversion channel. It can also act as check gate...... |
2214 | Head gate structure | 1 - The portion of the head regulator that houses control gates. 2 - Often used in the same sense as a head regulator...... |
3613 | Head gates, Inner gates, or Upper gates | Lock gates on the higher water-level side of the lock...... |
1150 | Head loss (in an aquifer) | The difference in height of the groundwater table in different parts of the same aquifer resulting from resistance to flow through the aquifer...... |
3084 | Head loss, or Loss of head | 1 - Energy lost (converted into heat) as the result of friction, impact or eddies, expressed as a `head` per unit of flow. 2 - See 4223 and 4560...... |
2213 | Head of a canal | The point where the supply is diverted into a canal from a reservoir, river, or parent canal...... |
5218 | Head of a drain | The upstream end of a drain...... |
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.