The background to this question is in Understanding difference between Coordinate System and Projection?
There @mdsumner commented:
WGS84 is not a cs, it's a datum.
On a couple of places online I have found: "WGS84 geographic coordinate system" mentioned. Is this an incorrect terminology?
WGS84" is a datum, but "WGS84" is also a geographic coordinate system defined by the "WGS84" datum?