Link on cells

Just to clarify as I am not sure the attachment helps to understand better what I need:

So if I have in a simple excel worksheet the cell A1 equal to "GGL". I am looking for a way to change the acronym on the cell A1 to display the disply name corresponding to the acronym. So in this case and as per the attachment it should read "Graig Lastname"

I would like to have that "switch" occurring by clicking on the A1 cell. Please check the "link.jpg" attachment.

Many thanks,
graig