In chemistry, a metal is an element that readily forms positive ions (cations) and has metallic bonds. Metals are sometimes described as a lattice of positive ions surrounded by a cloud of delocalized electrons.
OR a solid material which is typically hard, shiny, malleable, fusible, and ductile, with good electrical and thermal conductivity (e.g. iron, gold, silver, and aluminium, and alloys such as steel).
OR a metal is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. Metals are typically malleable or ductile Examples are copper, tin, iron, zinc and magnesium etc.
A nonmetal is an element that does not have the properties of a metal. Example chlorine, bromine, sulphur, argon, and iodine etc.
A metalloid is an element that has properties that are intermediate between those of metals and nonmetals. Metalloids can also be called semimetals or semiconductors. Examples of metalloids include boron, silicon, germanium, arsenic, antimony, tellurium, and polonium.