Vipasannā

Vipassanā (Pāli) or vipaśyanā (Sanskrit: विपश्यना; Burmese: 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 in conjunction with Samatha meditation is a necessary part of all Buddhist traditions. Therefore it is important to distinguish Vipassanā on the one hand, and the Vipassana movement on the other, which was represented in the Theravada-tradition by Ledi Sayadaw and Mogok Sayadaw and popularized by Mahasi Sayadaw, V.R. Dhiravamsa, S. N. Goenka.

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