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a two-component liquid rocket propellant that ignites when the two components (oxidizer and fuel) come into contact. For example, the oxidizer may be nitrogen tetroxide or a nitric acid oxidizer, and the fuel may be kerosine, hydrazine, or unsymmetrical dimethylhydra-zine. The use of hypergolic propellants simplifies the design of liquid-propellant rocket engines and improves engine reliability, since an ignition system is no longer necessary. Launching of the rocket is also facilitated by the more stable burning characteristics of the propellant.