pyro- or pyr-
1. Fire; heat: pyrotechnic.
2. Relating to the action of fire or heat: pyrography.
3. Fever: pyrogen.
4. Formed upon heating, by loss of water or another small molecule: pyrosulfuric acid.
[New Latin, from Greek puro-, from pūr, fire; see paəw in the Appendix of Indo-European roots.]
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