"Full size" denotes the traditional USGI 1911 frame size. Most 1911 pistols use full size magazines, such as Government length 5.0 inch and Commander length 4.25 inch 1911 pistols.
Full size grips have a measurement of 3.0625" of center-to-center between the grip screws.
Please note that many non-standard 1911's exist that take neither full size nor compact magazines, but instead must use proprietary magazines from their manufacturer. Some examples include the Springfield Armory EMP series pistols and the Kimber Micro series pistols.
If in doubt, please do not hesitate to contact us.