1. Of or relating to a rocket propellant consisting of fuel and an oxidizer that ignite spontaneously on contact.
2. Using such a fuel.
[From German Hypergol, a hypergolic fluid propellant : from hyper-, extreme (from Greek huper-; see HYPER-) + Greek ergon, work; see ERG1.]
hyper·gol′ (hīpər-gôl′, -gōl′, -gŏl′) n.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.