Irregular and Unstable

Irregular

Irregular adjective - Lacking in steadiness or regularity of occurrence.
Usage example: irregular mail delivery to the island

Unstable is a synonym for irregular in inconsistent topic. In some cases you can use "Unstable" instead an adjective "Irregular".

Nearby Words: irregularity, irregularly

Unstable

Unstable adjective - Likely to change frequently, suddenly, or unexpectedly.
Usage example: financial investors don't like an unstable economy

Irregular is a synonym for unstable in changeable topic. Sometimes you can use "Irregular" instead the word "Unstable" as an adjective or a noun.

Nearby Word: unstably
Cite this Source
Unstable and Irregular. (2016). Retrieved 2026, July 21, from https://thesaurus.plus/related/irregular/unstable
Irregular & Unstable. N.p., 2016. Web. 21 Jul. 2026. <https://thesaurus.plus/related/irregular/unstable>.
Unstable or Irregular. 2016. Accessed July 21, 2026. https://thesaurus.plus/related/irregular/unstable.
Google Ngram Viewer shows how "irregular" and "unstable" have occurred on timeline