Headlong
Headlong adverb - Without delay.
Usage example: had barely finished the last project when we went headlong into the next one
Instanter
Instanter adverb - Without delay.
Usage example: as soon as I had called out that answer, I instanter knew that it was wrong
Cite this Source
Instanter and Headlong. (2016). Retrieved 2026, August 14, from https://thesaurus.plus/related/headlong/instanter
Headlong & Instanter. N.p., 2016. Web. 14 Aug. 2026. <https://thesaurus.plus/related/headlong/instanter>.
Instanter or Headlong. 2016. Accessed August 14, 2026. https://thesaurus.plus/related/headlong/instanter.
Google Ngram Viewer shows how "headlong" and "instanter" have occurred on timeline