A part or aspect of something. For example, one dimension of public health is the settings in which public health work is carried out. A dimension is a property or construct whereby aspects of something can be distinguished (e.g. public health settings can be distinguished from public health functions and from public health methods). A dimension can also be described as a group of similar things that are from the same category of information (e.g. home and workplace settings are part of the settings dimension). Hence multi-dimensional, to have many aspects or dimensions (e.g. to provide a unified framework for multiple public health uses, a multi-dimensional classification is needed).