Adding columns in Pivot Table having common description

Hi,

I have made a Pivot Table (with 4000 rows and 80 columns) giving details of Employee Expenses for 2005-06 but it has columns which have similar description since we changed the Account Codes during the year and in some cases they mean the same thing like Breakfast, Lunch and Dinner all of which can be merged in one column for e.g. Meals.

Is there a way these similar columns could be added into one column within the pivot table itself?

Thanks in advance,

Sayvari