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.
The American Heritage Dictionary Blog
Check out our blog, updated regularly, for new words and revised definitions, interesting images from the 5th edition, discussions of usage, and more.