Most of the dictionaries in the Library are for reference use, reference copies can't be borrowed.  There may be additional copies of these dictionaries in the collection which you can borrow. 

• Search the Library using the title of the dictionary you want
• Click the title to view the copies available
• Reference copies don't go out, but other copies do:

e.g.

• Click the "Find" option to see where you can find the dictionary in the Library