Nidana


Nidana is a Sanskrit word that means "cause, motivation or occasion" depending on the context. The word is derived from ni and da. It appears in the Rigveda, such as hymn 10.114.2, and other Hindu scriptures, wherein it means "primary or first cause, linked cause"; in other contexts such as Rigveda 6.32.6, nidana refers to a rope or band that links, binds or fastens one thing to another, such as a horse to a cart.

Buddhism

Nidana is the term used to describe the standard introduction of a Buddhist sutra, where the formula "Thus have I heard" is followed by a description of the location and occasion on which the Buddha gave a particular teaching.
The other primary use of nidana in the Buddhist tradition is in the context of the 'Twelve Nidanas', also called the 'Twelve Links of Dependent Origination'. These links present the mechanistic basis of repeated birth, Samsara, and resultant Dukkha starting from avidyā.

Hinduism

The term Nidana appears in numerous ancient and medieval Hindu texts wherein it means "first cause, primary cause, original or essential cause". This includes the Upanishads that include theosophical speculations, as well as medical texts such as Sushruta Samhita and Charaka Samhita where a large sub-book is titled Nidana-sthana, as well as in chapters of the Puranas, wherein these discuss cause of disease or various natural phenomena.