|1.||[ adjective ] making a loud sharp sound as of a rifle shot or a breaking branch or a whip|
"lion tamers with their cracking whips"
|2.||[ noun ] the act of cracking something|
|Related terms:||breakage crack fracture|
|3.||[ noun ] a sudden sharp noise|
"the crack of a whip" "he heard the cracking of the ice" "he can hear the snap of a twig"
|Related terms:||noise crack snap|
|4.||[ adjective ] (informal) very good|
|Synonyms:||great swell bully keen dandy corking peachy neat nifty not_bad groovy slap-up cool smashing bang-up|
"a bully pulpit" "a neat sports car" "had a great time at the party" "you look simply smashing"
|Related terms:||colloquialism good|
|5.||[ noun ] (chemistry) the process whereby heavy molecules of naphtha or petroleum are broken down into hydrocarbons of lower molecular weight (especially in the oil-refining process)|
|Related terms:||chemical_process hydrocracking crack|