From the document's first part:
> A Conflict-free Replicated Data Type, or CRDT, is an umbrella term for any data structure that can be replicated and modified concurrently across multiple sites, and is guaranteed to converge without the need for a central authority to coordinate the changes.
To be fair, the definition is not in the bulleted abstract, it is in the first use of the term in the first section, which someone not familiar with CRDT might first scan, helpfully headlined “Intro to CRDTs”:
# First part: Intro to text CRDTs
A Conflict-free Replicated Data Type, or CRDT, is an umbrella term for any data structure that can be replicated and modified concurrently across multiple sites, and is guaranteed to converge without the need for a central authority to coordinate the changes.