Breath across languages
The Greek pneuma and Hebrew ruach, both usually translated "spirit," originally meant ordinary air or breath — pneuma is the root of the modern word "pneumatic." Latin spiritus carries the same double sense, and gives English its words for spirituality, respiration, inspire, and expire. Comparable ideas appear well beyond the Mediterranean: the Sanskrit prana names a life-sustaining "wind" or vital breath discussed in the Upanishads and used in Ayurveda and yogic thought, while Chinese medicine describes a similar vital-energy flow as qi.
The Sanskrit atman, closely tied to the Hindu idea of soul or self, likewise originates in a word for breath or "breath of life," before coming, especially in the Upanishads, to be identified with Brahman, the absolute reality said to pervade all beings.
A specific esoteric reading
Some esoteric writing — including that of the twentieth-century Gnostic teacher Samael Aun Weor, quoted in these terms — treats Atman as the ineffable, uncreated core of a person, to be sharply distinguished from the personality or ego. This is a teaching specific to that Gnostic lineage rather than a claim of Santo Daime doctrine, offered here for context on how the word "spirit" has been used comparatively across traditions.