- pyroA pyromaniac.
- pyrotechnicOf or relating to fireworks.
- pyroclasticMostly composed of rock fragments of volcanic origin or comminuted during an eruption.
- pyropeA variety of garnet, of a poppy or blood-red color, frequently with a tinge of orange. It is used as a gemstone.
- dipyreA type of scapolite (mineral).
- eupyrionA device historically used for obtaining instantaneous light, such as a lucifer match.
- pyrargyriteA sulfosalt mineral used as a silver ore; it is dark red or black in color with a metallic adamantine luster, a sulfide of antimony and silver, Ag₃SbS₃, and occurs in rhombohedral crystals.
- pyro-Fire, heat.
- pyroballogyThe study of artillery; the practice of using artillery as a weapon.
- pyrophorepyrophorus
- pyrophorusa substance capable of catching fire spontaneously on exposure to the air, especially in a finely divided state
- pyruvic acidA yellowish organic keto acid, 2-oxopropanoic acid, which occurs as an intermediate in many metabolic processes, especially glycolysis.