Concave
Valley
Valley noun - An area of lowland between hills or mountains.
Cite this Source
Valley and Concave. (2016). Retrieved 2026, August 14, from https://thesaurus.plus/related/concave/valley
Concave & Valley. N.p., 2016. Web. 14 Aug. 2026. <https://thesaurus.plus/related/concave/valley>.
Valley or Concave. 2016. Accessed August 14, 2026. https://thesaurus.plus/related/concave/valley.
Google Ngram Viewer shows how "concave" and "valley" have occurred on timeline