Irregular
Irregular adjective - Not having a level or smooth surface.
Usage example: although the moon looks smooth from here, it actually has a very bumpy and irregular surface
Undulating and irregular are semantically related. In some cases you can use "Undulating" instead an adjective "Irregular".
Nearby Words: irregularity, irregularly
Undulating
Irregular and undulating are semantically related. Sometimes you can use "Irregular" instead an adjective "Undulating".
Mutual synonyms
Cite this Source
Undulating and Irregular. (2016). Retrieved 2026, July 29, from https://thesaurus.plus/related/irregular/undulating
Irregular & Undulating. N.p., 2016. Web. 29 Jul. 2026. <https://thesaurus.plus/related/irregular/undulating>.
Undulating or Irregular. 2016. Accessed July 29, 2026. https://thesaurus.plus/related/irregular/undulating.
Google Ngram Viewer shows how "irregular" and "undulating" have occurred on timeline