Taṇhā (Pāli; Sanskrit: tṛṣṇā, also trishna) literally means “thirst,” and is commonly translated as craving or desire.
Taṇhā is defined as the craving or desire to hold onto pleasurable experiences, to be separated from painful or unpleasant experiences, and for neutral experiences or feelings not to decline.
Taṇhā is also identified as the eighth link in the Twelve Links of Dependent Origination.
It is this “thirst”, desire, greed, craving, manifesting itself in various ways, that gives rise to all forms of suffering and the continuity of beings. But it should not be taken as the first cause, for there is no first cause possible as, according to Buddhism, everything is relative and inter-dependent. Even this “thirst”, taṇhā, which is considered as the cause or origin of dukkha, depends for its arising (samudaya) on something else, which is sensation (vedanā), and sensation arises depending on contact (phassa), and so on and so forth goes on the circle which is known as Conditioned Genesis (Paṭicca-samuppāda)… So taṇhā, “thirst”, is not the first or the only cause of the arising of dukkha. But it is the most palpable and immediate cause, the “principal thing” and the “all-pervading thing”. Hence in certain places of the original Pali texts themselves the definition of samudaya or the origin of dukkha includes other defilements and impurities (kilesā, sāsavā dhammā), in addition to taṇhā “thirst” which is always given the first place. Within the necessarily limited space of our discussion, it will be sufficient if we remember that this “thirst” has as its centre the false idea of self arising out of ignorance.
Taṇhā is also identified as the eight link in the Twelve Links of Dependent Origination.
In the context of the twelve links, the emphasis is on the types of craving “that nourish the karmic potency that will produce the next lifetime.”
Taṇhā is a type of desire that can never be satisfied.
However, taṇnhā, meaning “thirst,” is not a chosen kind of desire, it’s a reflex. It’s the desire to pull something in and feed on it, the desire that’s never satisfied because it just shifts from one sense base to another, from one emotional need to the next, from one sense of achievement to another goal. It’s the desire that comes from a black hole of need, however small and manageable that need is. The Buddha said that regardless of its specific topics, this thirst relates to three channels: sense-craving (kāmataṇhā); craving to be something, to unite with an experience (bhavataṇhā); and craving to be nothing, or to dissociate from an experience (vibhavataṇhā).
via: Taṇhā @wikipedia