Excel formulae to code bank transactions

I want to code my bank transactions by running formulae over them from 2 x lists I have created. I want to do this via excel, so I can do it on the computer. 1) I manually download data from a bank account into Excel; 2) I run a formula over the description column that says: (if the description column (C) contains the keyword "blah" from the Keyword List, then assign it "category" from the Category List. I want to be able to update the Keyword and Category List. I want to be able to have more than one keywork for each category. Not all categories have keywords.