Purport

Arjuna asked seven questions, to which Bhagvan Shri Krishna replied categorically and specifically. The specific terms explained are as follows

1 Bramhan:
Bramhan is one of the most important concepts of Sanatan Dharma and one of the core Subjects in Shrutis (Vedas & Upanishads). Bramh Sutra in Vedas is dedicated specifically to this very subject.

Though described in most of the Sanatan Scriptures, the concept of Bramhan is still not correctly understood by most of people. The biggest confusion regarding Bramhan, whether Bramhan is God or Bramhan means God? Or Bramhan is something which is used as a synonym for God but is not God.
There is no better place to understand this subtle concept than in Shrimad Bhagvad Gita.

In the above Shlokas, Branhan is defined using two clear words. Akshara means Indestructible or imperishable and Paramam means the supreme. Therefore Bramhan is the supreme imperishable entity. No doubts here that Bramhan is Supreme and nothing exists beyond it. This automatically gives the conclusion that there are only two possibilities, 1 Bramhan is another terminology for God or 2. Bramhan is an inseparable part of God and hence synonymous with God.
The clarification of this can be found by looking at other Shloka
, and it is at least synonymous with God. Though above Shlokas still does not say if Bramhan=God and the meaning still open to different interpretations. The Translation by Adi Shankara and Ramanujacharya is also silent on this question. However, Madhvacharya deriving meaning from other parameters used in above Shloka and the characteristics defined elsewhere in Shrimad Bhagvad Gita concluded

But one question still remains. Does Bramhan

Though one doubts remain here, does Bramhan and God are synonym with each other or are they different? The answer to this question can be found in Sh 3 of Chapter 14, which describes Brmhan as eternal potency of Bhagvan Shri Krishna.

O Bharat! My Primeval material is Bramhan. In it impregnate(place the seeds of all life) and pulsate my solemn promise(my will) on the evolution of the world in it. Through this, all the creations come into existence(Shrimad Bhagvad Gita:Ch14:Sh3)

This Shloka makes it very clear that Bramhan is the first potency of Bhagvan Shri Krishna and the source of all lives in this universe. Bramhan does not equal to God or Bramhan does not mean God but since it is inseparable part of God and can be used as a synonym for God. That explains the variations in the explanation of Bramhan in different scriptures.

2. Adhyatma
There are some variations in explanation of this term. Shri Ramanujacharya explains Adhyatma as the svabhava(nature) of living beings. But Shri Madhvacharya and Adi Shankaracharya explain Adhyatma as the internal characteristic of Bramhan which extends the life in individual living beings. No matter what meaning one takes, it still leads to the same conclusion that Adhyatma refers to the soul.

3. Karma
Most of the time people take Karma as the activities done by living being mostly by humans. But Karma has a wide meaning. It's a creative force that makes things happen in this entire universe. Any movement, any physical or chemical reaction or biological change is Karma. K

4. Adhibhuta
Any perishable living or non-living entity is called as Adhibhuta. In other sense, Adhibhuta is the opposite of Bramhan.

5. Adhidaiva
This term again is described in a different way by different commentators. Shri Madhavacharya defined Adhidaiva as the nature of divinities, whereas Ramanujacharya defined Adhidaiva as superior to devatas(devas). Shri Prabhupada defined Adhidaiva as the source of forms of the Universe. In my view, the meanings by Madhavacharya and Ramanujacharya appears correct. Shri Adi Shankara to indicates the same meaning, the one who is the source of all deities.

6. Adhiyajna
Yajna is another term which is one of the core subject of Vedas yet understood by very few. Many people take meaning of Yajna as the rituals of Havana, chanting matras etc. But Yajna as Karma is a wide term and includes all processes in living beings where there is one entity that is consumed and another entity consumes it. When we do rituals of Yajna we actually replicate the same process. The process is called as offerings. Yajna is the force of change in this material world and Adhiyajna hence is one who consumes all the changes. Bhagvan Shri Krishna explained he himself is the Adhijyana. To remind readers, Bhagvan Shri Krishna has displayed his Vishvarupa where he has shown how he is consuming everything at one end and producing at other ends, completing the cycle.

7. Who resides in this body as Adhiyajna the principle of change.

Bhagvan Shri Krishna answered, he himself is the principle of Yajna, which resides in the body of living beings. Through this principle, all changes come into play and lives move

Thus Shri Krishna answer all 7 questions asked by Arjuna