Source: Schema.org v30.1 vocabulary. Official utterances property definition.
What does utterances mean?
Text of an utterances (spoken words, lyrics etc.) that occurs at a certain section of a media object, represented as a [[HyperTocEntry]].
Used on types (domainIncludes)
Expected value types (rangeIncludes)
Schema.org domainIncludes and rangeIncludes are descriptive guidance, not strict validation prohibitions. Check the official reference for updates.
Related reference
Browse all Schema.org types and properties · Google feature support status