First
First adjective - Coming before all others in importance.
Usage example: there are a number of reasons we can't go, but the first is that we don't have the money
Greatest is a synonym for first in foremost topic. In some cases you can use "Greatest" instead the word "First" as an adjective or a noun, when it comes to topics like highest in importance.
Nearby Word: firstly
Greatest
Greatest adjective - Coming before all others in importance.
Usage example: the greatest achievement in the history of cinema
Mutual synonyms
Cite this Source
Greatest and First. (2016). Retrieved 2026, July 27, from https://thesaurus.plus/related/first/greatest
First & Greatest. N.p., 2016. Web. 27 Jul. 2026. <https://thesaurus.plus/related/first/greatest>.
Greatest or First. 2016. Accessed July 27, 2026. https://thesaurus.plus/related/first/greatest.
Google Ngram Viewer shows how "first" and "greatest" have occurred on timeline