The English word spirit (from Latin spiritus "breath") has many differing meanings and connotations, most of them relating to a non-corporeal substance contrasted with the material body. The spirit of a living thing usually refers to or explains its consciousness. The notions of a person's "spirit" and "soul" often also overlap, as both contrast with body and both are understood as surviving the bodily death in religion and occultism, and "spirit" can also have the sense of "ghost", i.e. a manifestation of the spirit of a deceased person.

The term may also refer to any incorporeal or immaterial being, such as demons or deities, in Christianity specifically the Holy Spirit experienced by the disciples at Pentecost.