As per JENKINS-27268, all instances of "slave" were renamed to "agent" throughout the Jenkins core UI, and the changes were merged into the Jenkins 2.0 branch.

To be consistent| with the new naming, and as per the terminology sweep, and the proposed renaming in JENKINS-33007, I believe it would be good if node was renamed to agent in the Pipeline DSL.

For backwards compatibility, node should most likely still be supported, as an alias for agent.