Vipaśyanā

Vipassanā (Pāli) or vipaśyanā (Sanskrit: विपश्यना; Myanmar: ဝိပဿနာ; Sinhalese: විපස්සනා; Chinese: 觀 guān; Standard Tibetan: ལྷག་མཐོང་, lhaktong; Wyl. lhag mthong) in the Buddhist tradition means insight into the true nature of reality, namely as the Three marks of existence: impermanence, suffering or unsatisfactoriness, and the realisation of non-self. Presectarian Buddhism emphasized the practice of Dhyana, but early in the history of Buddhism Vipassanā gained a prominent place in the teachings.

Vipassanā meditation has been reintroduced in the Theravada-tradition by Ledi Sayadaw and Mogok Sayadaw and popularized by Mahasi Sayadaw,S. N. Goenka, and the Vipassana movement, in which mindfulness of breathing and of thoughts, feelings and actions are being used to gain insight into the true nature of reality. Due to the popularity of Vipassanā-meditation, the mindfulness of breathing has gained further popularity in the west as mindfulness.

Vipassanā is a Pali word from the Sanskrit prefix "vi-" and verbal root paś. It is often translated as "insight" or "clear-seeing," though, the "in-" prefix may be misleading; "vi" in Indo-Aryan languages is equivalent to the Latin "dis." The "vi" in vipassanā may then mean to see into, see through or to see 'in a special way.' Alternatively, the "vi" can function as an intensive, and thus vipassanā may mean "seeing deeply."

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Wikipedia