In Hebrew the word for spirit is ruwahk. It means "breath, wind, spirit, impulse, air, vivacity, or disposition."
The Greek word for spirit is pneuma and means literally "wind, breath" and can be translated correctly as "spirit, breath, wind, soul"...another form, pneumaticas means the inner breath, or life force.
The Hebrew word for soul is nephesh. It means "soul, living being, appetites, desire, emotion, passion, that which breathes, the inner being, or person."
The Greek word psuche (from which we get psyche), most often translated "soul" means literally "life." The word soul means "center of life."
So while they are different words, they have very similar meanings and can be used interchangeably depending on context. The spirit is considered more the inner life, the real you....and the soul descibes the passions, desires, emotions, and focus of that inner life.
PW