1) Computer file format 
Metafile is a generic term for a file format that can store multiple types of data. This commonly includes graphics file formats. These graphics files can contain raster, vector, and type data. A common use for these files is to provide support for an operating system`s computer graphics; e.g., Microsoft Windows uses Windows Metafile, and Mac OS ....
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Files that can be shared by more than one application program
Files that can be shared by more than one application program. 
A memory or disc file containing an image in the form of drawing instructions, rather than as a Bit Image. See also Vector Image.
A file format that contains both bitmap and vector data, that can be used on different machines and in different applications.