Updated and written by Helga Tawil Souri, October 2023
Books (many of these are available digitally by logging in to NYU library), some of these are explicitly about media studies, others are about social theory/critical theory.
Oxford Encyclopedia of Communication and Critical Cultural Studies: https://www.oxfordreference.com/display/10.1093/acref/9780190459611.001.0001/acref-9780190459611
Key Concepts in Communication and Cultural Studies: https://www.taylorfrancis.com/books/mono/10.4324/9780203814284/communication-cultural-media-studies-john-hartley
Key Words in Media Studies: https://nyupress.org/9781479859610/keywords-for-media-studies/
The Sage Handbook of Media Studies: https://us.sagepub.com/en-us/nam/the-sage-handbook-of-media-studies/book224694
The International Encyclopedia of Communication: https://onlinelibrary.wiley.com/doi/book/10.1002/9781405186407
Blackwell Dictionary on Modern Social Thought: https://onlinelibrary.wiley.com/doi/book/10.1002/9780470999028
Websites:
Internet Encyclopedia of Philosophy: https://iep.utm.edu/
Online glossary: https://opentextbc.ca/mediastudies101/back-matter/glossary/ (this one is very simple and is just a dictionary of common terms, but doesn't get into the meaning or theoretical approaches)
Archived websites (no longer updated but still useful):
Contemporary Philosophy, Critical Theory and Postmodern Thought https://web.archive.org/web/20140219152837/http://carbon.ucdenver.edu/~mryder/itc/postmodern.html