additionalType

Thing > Property > additionalType

An additional type for the item, typically used for adding more specific types from external vocabularies in microdata syntax. This is a relationship between something and a class that the thing is in. In RDFa syntax, it is better to use the native RDFa syntax - the 'typeof' attribute - for multiple types. Schema.org tools may have only weaker understanding of extra types, in particular those defined externally.

Usage: Between 10,000 and 50,000 domains
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Values expected to be one of these types
URL
Used on these types
Thing
Super-properties
http://www.w3.org/1999/02/22-rdf-syntax-ns#type

Schema Version 2.1