What are field definitions and how do I find them?

A field definition is a special node that stores the settings of a field. It looks like this:

1. A field definition node
2. A field

To grab the field definition from a field, put your cursor in the field name, then press copy (Cmd/Ctrl+C) and put your cursor on an empty node and paste (Cmd/Ctrl+V). That gives you a reference to the field definition. Then you can run the command Bring referenced nodes here to swap the reference with the actual node.

For more information on field definitions, go here.