Q. where can I find definitions to words

What kind of dictionaries are you looking for? English language? translation? 

You can search the library catalog on the Library's webpage or directly at the following link: http://discovery.lib.liu.edu/iii/encore/search?formids=target&lang=eng&suite=def&reservedids=lang%2Csuite&submitmode=&submitname=&target=dictionaries&Go.x=12&Go.y=20

You can also visit the 3rd floor of the library to consult with the dictionaries in the Quiet Study area (Reference Collection). 

There are also plenty of online dictionaries: http://www.refdesk.com/factdict.html