Mick's Communication, Cultural and Media Studies
Extensive list of interlinked definitions of concepts related to cultural studies and media ecology.

Communications Central
Links to resources and definitions related primarily to semiotics, interpersonal communication, organizational communication, health communication, and nonverbal communication. From Governor's State University.

Claes de Vreese
Resource for teaching and research on political communication, public opinion, media effects, campaigns, and media and politics.