Key
Key adjective - Coming before all others in importance.
Usage example: maintains that Sir Isaac Newton remains the key figure in physical science
Leading is a synonym for key in essential topic. In some cases you can use "Leading" instead the word "Key" as an adjective or a noun, when it comes to topics like main, important, crucial. popular alternative
Leading
Leading adjective - Coming before all others in importance.
Usage example: they are the leading suppliers of processed meat in the country
Key is a synonym for leading in main topic. You can use "Key" instead the word "Leading" as an adjective or a noun, if it concerns topics such as principal, important. popular alternative
Mutual synonyms
Both words in one sentence
-
The key event here is Columbus leading a new Crusade to retake the Holy Land instead of sailing West.
Source: Alternate History Wank - His Nobel Prize was for the photoelectric effect instead (though his explanation was one of the key points leading to the development of quantum mechanics).
Source: Consolation Award - A botched ransom drop is one of the key turning points in Man on Fire, leading Creasy to vow revenge on Pita's kidnappers.
Source: Ransom Drop
Cite this Source
Leading and Key. (2016). Retrieved 2026, August 16, from https://thesaurus.plus/related/key/leading
Key & Leading. N.p., 2016. Web. 16 Aug. 2026. <https://thesaurus.plus/related/key/leading>.
Leading or Key. 2016. Accessed August 16, 2026. https://thesaurus.plus/related/key/leading.
Google Ngram Viewer shows how "key" and "leading" have occurred on timeline