chih-kuan (Chinese). 1. A compound consisting of two words meaning ‘stop’ and ‘observe’. The words correspond to the Sanskrit śamatha (calming) and vipaśyanā (insight). These have been interpreted in various ways. Chih can mean either to suppress mental activity in order to focus on a single object of meditation, to withdraw the mind from sensory engagement with the external world, or (in some Pure Land texts) to desist from evil actions. Kuan can mean to observe the natural workings of the mind, to contemplate or observe a mental object closely, or to investigate the nature of reality.

2. In the T'ien-t'ai school's system of meditation, as laid out in Chih-i's manual Mo-ho chih-kuan (The Great Calming and Insight), both chih and kuan are glossed in three ways. Chih means (a) to calm the mind and suspend its agitated, impure thoughts; (b) to fix the mind on the present moment; and (c) to realize the non-duality of the agitated mind and the calm mind as equal manifestations of reality. Kuan has the three meanings of: (a) to dissipate perturbations of the mind through wisdom that sees through their illusory nature; (b) to gain insight into suchness (tathatā), the fundamental nature of all things; and (c) to gain insight into the fundamental equality of non-contemplation and contemplation from the perspective of suchness.

A Dictionary of Buddhism, Oxford University Press, 2003, 2004 (which is available in electronic version from answer.com)