Bhāva is a Sanskrit term denoting the mental transformation resulting from the perception of a feeling or emotion, commonly known as Rasa. To comprehend this process of mental change arising from emotion or feeling, it is essential to consider four elements:

1. Sthāyī Bhāva - This is the initial transformation in the mind triggered by an emotion or feeling. Sthāyī Bhāva is described as the enduring change that occurs in the mind when a specific feeling takes hold. Once the particular emotion fades away, the alteration within the mind also dissipates, returning it to a normal state. The term "Sthāyī" implies endurance, as this Bhāva's existence relies on the presence of the emotion.

2. Sañcārī Bhāva or Vyabhicārī Bhāva - This represents another state of the mind, which, although secondary, remains complementary to the first. What emanates from the first is termed Sañcārī Bhāva in relation to Sthāyī Bhāva.

3. Vibhāva - The elements contributing to a Bhāva are referred to as Vibhāva. These can include various factors like music, spring, war, fire, a pair of lovers, etc., essentially forming the context or ingredients of a particular emotional state.

4. Anubhāva - All actions that express Bhāva are termed Anubhāva. Examples of Anubhāva include actions such as playing with eyebrows, jumping, smiling, or winking.

Each Rasa, or aesthetic essence, possesses its Sthāyī Bhāva, Sañcārī Bhāva, Vibhāva, and Anubhāva. (Refer to Rasa for further details.)