Genre of acting without much action

• Naturalistic genre with hard-to-hear dialogue

Wikipedia Word definitions in Wikipedia
Mumblecore is a subgenre of independent film characterized by naturalistic acting and dialogue (often improvised), low-budget film production, an emphasis on dialogue over plot, and a focus on the personal relationships of people in their 20s and 30s. Filmmakers ...

Wiktionary Word definitions in Wiktionary
n. (label en film) An American independent film movement of the early twenty-first century, characterised by low-budget production, focus on personal relationships between twentysomethings, improvised scripts, and non-professional actors.