Waste is any product which is no longer of use for what it was initially intended for. Waste can also be define as any product dispose or discarded after primary use.
It is worth mentioning that waste can be a by-product or a resource needed for the production of something valuable for example some waste are transformed into compost.
   
  There are different definition of waste according to some organizations, agencies and bodies involved in Waste, waste management as seen below;

1) Article 5 of the Basel Convention : 
Define Wastes as any  substance or objects which are disposed of or are intended to be disposed of or are required to be disposed of by the provisions of national law”.

2)Waste Framework Directive of the European Union, Article 3  
Define waste as  any substance or object which the holder discards or intends or is required to discard

3) OECD defines Waste as   substances or objects, other than radioactive materials covered by other international agreements, which: i) are disposed of or are being recovered; or ii) are intended to be disposed of or recovered; or iii) are required, by the provisions of national law, to be disposed of or recovered.

4) United Nations Statistics Division describes waste as "materials that are not prime products (that is, products produced for the market) for which the generator has no further use in terms of his/her own purposes of production, transformation or consumption, and of which he/she wants to dispose. Wastes may be generated during the extraction of raw materials, the processing of raw materials into intermediate and final products, the consumption of final products, and other human activities. Residuals recycled or reused at the place of generation are excluded

  Despite which definition is accepted for waste, it is important for us to continue raising awareness at the local and International level if we expect to achieve sustainable development. The rate of Environmental pollution, depletion of nature's resources is alarming. Our water bodies are becoming toxic everyday, same like the air, land and not forgotten the destruction of the ozone layer.
  We must continue to raise awareness on proper, effective and efficient methods of managing waste