Dig down
Root and dig down are semantically related. in investigate topic. In some cases you can use "Root" instead a verb "Dig down", when it comes to topics like delve into.
Root
Root verb - To set solidly in or as if in surrounding matter.
Cite this Source
Root and Dig down. (2016). Retrieved 2026, July 22, from https://thesaurus.plus/related/dig_down/root
Dig down & Root. N.p., 2016. Web. 22 Jul. 2026. <https://thesaurus.plus/related/dig_down/root>.
Root or Dig down. 2016. Accessed July 22, 2026. https://thesaurus.plus/related/dig_down/root.
Google Ngram Viewer shows how "dig down" and "root" have occurred on timeline