Bhagavad Gītā Chapter Thirteen Title

kṣetra kṣetrajña vibhāga yogaḥ

The Yoga of the Distinction between the Field and the Knower of the Field.

kśetra - the fieldjña - knowingvibhāga - distinctionyoga - the act of yoking

Commentaries and Reflections

Commentary by Paul Harvey:

The Yoga of distinction.
What is and what is not Matter.