It's related to the Greek word "pneuma," which also means "breath" and has associations with "spirit," "life," and "wind."
Here are some examples of words derived from "spir":
* Spirited: full of energy and enthusiasm
* Aspire: to aim for something higher or better
* Conspire: to secretly plan to do something harmful or illegal
* Respire: to breathe
* Inspire: to fill someone with the urge or ability to do or feel something
* Expire: to come to an end or cease to be valid
* Spiral: a curve that winds around a central point
As you can see, the meaning of "spir" is reflected in the various words that it forms, often relating to movement, energy, or life force.