thiên

Thiên is a Vietnamese word derived from the Sino-Vietnamese character 天, meaning "heaven" or "sky." In Vietnamese, it functions both as a standalone term in certain phrases and as a semantic element in many compounds, conveying celestial or elevated sense.

Common uses and expressions include thiên nhiên (nature), thiên văn (astronomy), and thiên văn học (the science of astronomy). Other widely used forms are thiên đường (paradise or heaven), thiên tai (natural disaster), và thiên hạ (the world or the realm of people). The phrase thiên thời địa lợi nhân hòa appears in traditional discourse to denote favorable conditions—timing from heaven, advantageous geography, and harmony among people. In cosmological and cultural contexts, terms such as thiên giới (the celestial realm) and thiên thần (angel) also incorporate thiê n as a prefix or component.

Thiên is also a common element in Vietnamese personal names. As a given-name syllable, it evokes celestial or noble qualities and is frequently used in male names, though it also appears in female names in contemporary use. Examples of combinations include Thiên An, Thiên Minh, and Thiên Long, among many others. When used in names, thiê n carries connotations of grandeur, purity, or a connection to heaven.

Notes and distinctions: thiê n should not be confused with thiền, which means Zen or meditation in Vietnamese. The two are etymologically distinct despite similar spelling in some contexts and may appear in different compound words and phrases.