Good Morning, Afternoon, Evening (Depending on where you are)

I have put together a TimeSheet that allows the user to select a type of
leave that a person may have, e.g. Annual Leave, Sick, Bereavement Leave etc.


Currenty I have a list of names in columns and dates in rows and when a
person is on leave the user drops a list down and selects the relevant leave.
However, what I want is rather than the whole word to appear e.g. Annual
Leave, I want a short code to appear e.g. A.L.


So the user sees the full description in the drop down list but all that is
entered into the cell is the short code.

I can not use a Macro due to IT issues, I think if it can be done then it is
the Data Validation function, but not too sure what to do then. Its almost a
VLookup command but if you enter this in the cell and then create a drop down
list you get a circular reference, which is not good!

I hope I have explained myself clearly enough and thank you in advance for
any help you can offer.