Mana is not among the original three Buddhist poisons; it enters the scheme when the list is widened to five in later Abhidharma and Vajrayana literature, alongside raga, dvesha, moha and irshya, and it names the conceit that measures the self against others, whether by ranking oneself above them, alongside them or even, in a subtler analysis the tradition insists on, below them, since self abasement is still a comparison and still a clinging to a fixed self image.
The Princeton Dictionary of Buddhism treats it as a persistent affliction that survives well into advanced stages of practice, harder to notice than craving or anger because it can disguise itself as humility. Jain metaphysics places mana on an entirely different structural footing, as one of four kashayas, passions, alongside krodha, maya and lobha, and the kashayas are not simply moral failings to Jain physics but literal mechanisms: the Tattvartha Sutra describes them as the stickiness by which karmic matter, otherwise inert particles pervading the universe, adheres to the soul, jiva, and weighs it down through further rebirths. A soul entirely free of kashaya cannot accumulate new karmic bondage even while still acting in the world, which is why Jain ascetic practice targets the kashayas directly rather than treating right action alone as sufficient.