Meaning of hypergolic

hy•per•gol•ic

Pronunciation: (hī"pur-gô'lik, -gol'ik), [key]
— adj.
  1. (esp. of rocket-fuel propellant constituents) igniting spontaneously upon contact with a complementary substance.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.