The phrase "captive audience" refers to a group of people who are unable to leave or escape from a particular situation, such as a lecture or a performance. There are many synonyms for this phrase, including "captive market," "trapped audience," "obligated audience," "restricted audience," and "compelled audience." All of these phrases suggest a sense of confinement or limitation on the audience's ability to leave or disengage from the presentation or performance. The use of such phrases can be seen in contexts ranging from advertising and marketing to public speaking and entertainment. Overall, the term "captive audience" is a common idiom that represents an audience that has limited choices or options.