A colander is a perforated bowl, made of stainless steel, aluminum, or plastic, that is used to drain the liquid from pasta, vegetables, salad greens, and other foods. The holes in a colander are large, making it unsuitable for anything but draining away excess liquid from food items that are large enough not to pass through the perforations.
Some people refer to the colander as a pasta strainer. The words strainer or colander are basically interchangeable except that the word strainer does not denote any particular size, whether fine or large, to the perforations, and may be made of fine mesh wire, and be of any of several basic shapes, such as bowl or cone-shaped. A colander, however, is always shaped like a bowl and has large perforations.
A colander also usually has legs so that it can stand on its own. It is best for cleaning or draining larger pieces of food. All strainers and colanders are types of sieves, which is any perforated device used to separate different elements, whether wet or dry.
The exact origin of the word colander is unknown, but other early spelling is cullender and colyndore. The word most likely derives from the Latin word colum, meaning sieve or filter. From colum came the verb colare meaning to flow, filter, or strain, and having the sense of “to pass while another does not pass.” From the words colum and colare came the Vulgar Latin noun colator Colator is assumed to be the origin of the Old Provençal (Occitan) colador. From here the Middle English colyndore was derived, the n/ being added in English.
The word percolate also comes from colare, with per meaning “through” so that percolate means “to pass or flow through. Colation refers to the act of straining and the product of straining is called a colature.