How can I access an online English dictionary?

The Library subscribes to Oxford Reference Online.  This database gives you access to reference titles including English language dictionaries. You may find subject-specific dictionaries more useful than general ones  Eg.Concise Oxford Dictionary of Linguistics

As you browse through Oxford Reference, you may find results that range from short-entry, general reference to more in-depth articles on specialized subjects.  To access this resource, go to databases to search for Oxford Reference Online. Then select Reference Type > English dictionaries or Bilingual dictionaries