You can use dictionaries, encyclopedias and other reference works to:
Some useful dictionaries and encyclopedias are listed below.
Some online encyclopedias include:
Encyclopedia of linguistics / edited by Philipp Strazny (2007)
Concise encyclopedia of sociolinguistics / edited by Rajend Mesthrie (2001)
The Routledge encyclopedia of second language acquisition / edited by Peter Robinson (2013)
Encyclopedia of language and education, 2nd ed. / series editor by Nancy Hornberger (2007)
Encyclopedia of language and education, 3rd ed. / series editor Stephen May (2017)
The following sources are available in print form in the library, many at classmark P 29 on floor 5:
The Cambridge Encyclopedia of Language by David Crystal (2010)
The Encyclopedia of Applied Linguistics by Carol A. Chapelle (Editor) (2013)
Encyclopedia of Language and Linguistics by Keith Brown (Editor-In-Chief) (2006)
The Routledge Linguistics Encyclopedia by Kirsten Malmkjaer (Editor) (2010)
If you are researching aspects of Sociolinguistics and need help with sociological concepts then please take a look at the range of online academic encyclopedias listed on the Sociology subject guide
Language dictionaries are inter-filed with the loanable books on floor 5. You can use the keyword "dictionary" in library search and combine with other keywords (e.g. "english language", "slang", etc.)