Bliss is an emotional state that is characterized by perfect happiness (feelings of enjoyment, pleasure, and satisfaction).
bliss: Tibetan: de nyam.
In Vajrayana, there are four types of bliss:
1. blissful feeling - to be free from adverse conditions of disharmony.
2. conceptual bliss - to be free from the pain of concepts.
3. non-dual bliss - to be free from clinging to dualistic fixations.
4. unconditioned bliss - to be free from causes and conditions.
When the experiences of clarity, non-thought and bliss appear, a practitioner can become attached to these, thus giving rise to a hindrance called the "defect of meditation."
One who does not detach, strays into three states of existence (the realms of desire, form, and formlessness).