The UIUC Library has a large collection of print dictionaries, many of which can be checked out. To find a monolingual English dictionary, search the Classic Catalog using the subject heading English Language Dictionaries (Tips For Searching the Online Catalog).or the the VuFind Catalog using the descriptor English Dictionary. To find bilingual dictionaries, search the Online Catalog using subject headings similar to French Language Dictionaries English. Instead of "French," substitute whatever language you are searching for.
Monolingual Dictionaries: Online
Monolingual Dictionaries: Print
Etymological and historical dictionaries
Wallwork, Adrian. English for academic research : vocabulary exercises. New York : Springer, 2013.
Academic Word Lists - compiled by a scholar in New Zealand, these lists of commonly used academic words are organized by usage frequency.
Academic English Cafe - there are vocabulary quizzes as well as spelling, writing, and grammar quizzes. The writing prompts may also be useful for practicing persuasive and descriptive writing skills.
Word A Day - a new, unusual English word is posted each day with a definition, audio pronunciation, and example usage. Great for native speakers and advanced language learners alike!
200 Vocabulary Exercises - visual exercises in vocabulary from the University of Victoria English Language Centre.