Decomposition of a complex substance by the application of steam, a catalyst, or heat, especially the breaking of petroleum molecules into shorter molecules to extract low-boiling fractions such as gasoline.
Excellent; great: had a cracking time at the dance.
Used as an intensive: a cracking good show.
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.