Guileless
Plain
Plain adjective - Free in expressing one's true feelings and opinions.
Usage example: their piano teacher is honest and plain, if not always tactful
Guileless is a synonym for plain in straightforward topic. Sometimes you can use "Guileless" instead an adjective "Plain", if it concerns topics such as behaviour, straightforward in speech.
Mutual synonyms
Cite this Source
Plain and Guileless. (2016). Retrieved 2026, August 16, from https://thesaurus.plus/related/guileless/plain
Guileless & Plain. N.p., 2016. Web. 16 Aug. 2026. <https://thesaurus.plus/related/guileless/plain>.
Plain or Guileless. 2016. Accessed August 16, 2026. https://thesaurus.plus/related/guileless/plain.
Google Ngram Viewer shows how "guileless" and "plain" have occurred on timeline