The term spirit translates from Greek 'pneuma' and Hebrew 'ruach'. It is a translation that today we must consider, however, partly because 'pneuma' and 'ruach', both in antiquity meant, while spirit, literally air, the simple and common air of nature. From Greek 'pneuma' comes, for example, something so far from any form of spirituality as the word ‘pneumatic’. Air and spirit are very different things for us, radically different we must say in our modern languages, but curiously were interchangeable in ancient Greek and Hebrew. What is now a marked double meaning was originally a complete identity of both concepts.
The Latin 'spiritus', besides referring to what we mean by spirit, also meant air or 'air breathing' or breath, invariably as the Greek and Hebrew words we have seen. 'Spiritus' is the root of words related to both modern meanings as are spirituality, respiration, inspire and expire.
Neither escapes of the standard the Latin word for soul. 'Anemos', besides the sense of soul, means blow, breath, wind. Hence, for example, the word anemometer, which refers to the apparatus used to measure the intensity of the wind. The Latin 'anemos', as the spirit, is the breath of life, the basis of life, because breath is the proof that one is alive, common to animals and people.
The Arab 'ruh' well just have a sense of spirit or soul, while one of wind or air.
Similarly, the Hindu notion of 'prana', which means breath, in Sanskrit means 'primary and all round Life Energy'. 'Prana' is described in the Upanishads as a physical principle of air that permeates all forms of life, which is life maintainer of body and also, at the same time, is the origin of the variable thought. It occurs mainly through breath (although the blood and other fluids). In Ayurveda, tantra and Tibetan medicine ‘prana vayu’ is the basic ‘vayu’ (that is: wind, air) from which all the other vayus arise. “Prana vayu” is beating of the heart and breathing. Prana enters the body through the breath and is sent to every cell through the circulatory system.
In Chinese medicine, especially acupuncture and its derivations, the equivalent of prana is qi. Qi is literally breath and mood, is an active principle forming part of any living thing which has to be understood as a ‘vital energy flow’. Qi is an air energy that continuously flows by nature, and a disruption of its free flow in the body is the basis of physical and psychological disorders.
The Hindu word for soul, 'atman' in Sanskrit means breath again. In Hindu thought, the 'atman' originally was the 'breath of life' or 'life principle' of living beings. Later, on one hand, takes the modern sense westernmost 'inner reality' or 'inner self', but on the other side, especially from the Upanishads, the 'atman' is increasingly identified with the 'brahman', the absolute that penetrates and surrounds all beings.