Nidana

Nidāna (निदान) is a Sanskrit and Pali word that means "cause, motivation or occasion" depending on the context. The word is derived from the Sanskrit prefix ni- (नि; "down", "into") plus the root dā (दा; "to bind"), forming the verb nidā (निदा; "to bind on, fasten"). This in turn yields the noun nidāna (निदान; lit. "a band, rope or halter"). 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, nidāna refers to the literal meaning of a rope or band that links, binds or fastens one thing to another, such as a horse to a cart. The word has been borrowed into modern languages such as Hindi and Marathi to mean "diagnosis" or "primary cause" among others.