When searching the internet for "Qi" (气/氣), a person finds definitions like the ones shown below. Defining Qi is not just an English-Chinese translation problem. Qi, like the words happiness or love, defy a simple definition because they are a result of our experiences. A Chinese proverb states, "To know the road ahead, ask those coming back". Qi Encyclopedia is a collection of short informative essays from experts who have travelled the road and share their thoughts.
Qì=Pinyin; Ch'i=Wades/Giles; Traditional Chinese=氣; Simplified Chinese=气. A literal translation of "qi" is "breath", "air", "or gas."
Encyclopaedia Britannica: In Chinese philosophy, the ethereal substance of which everything is composed. Early Daoist philosophers and alchemists regarded it as a vital force associated with breath and bodily fluids and sought to control its movement within the body in order to achieve longevity and spiritual power. Manipulation of qi is central to Chinese meditation, medicine, and martial arts. In the 10th–13th centuries Neo-Confucianism regarded qi as emanating from the Great Ultimate by way of li, the ordering principle of the universe, transformed into the elements through yin and yang. (1)
Cambridge Advanced Learner's Dictionary: "Chi". noun. In some systems of Chinese medicine and exercise, the most important energy that a person has. (2)
Oxford Dictionaries: noun. The circulating life force whose existence and properties are the basis of much Chinese philosophy and medicine. Origin: from Chinese qì, literally 'air, breath'. (3)
TheFreeDictionary.com: noun Qi - the circulating life energy that in Chinese philosophy is thought to be inherent in all things; in traditional Chinese medicine the balance of negative and positive forms in the body is believed to be essential for good health. (4)
Vocabulary.com: In Chinese philosophy, qi, also spelled chi or ch’i, is the life force that every person and thing has. Chinese medicine and acupuncture both address the concept of qi; if you’re feeling a little under the weather, an unbalanced qi may be the culprit. Martial arts also uses the concept: if you’ve ever practiced tai chi, then you’re already familiar with qi. (5)