Plain
Undercover
Undercover adjective - Undertaken or done so as to escape being observed or known by others.
Usage example: an undercover operation to infiltrate the terrorist organization
Plain is an antonym for undercover.
Both words in one sentence
- Averted for some unqualified "rescuers" - the occasional undercover videos has the main suspect(s) seen treating the "rescued" animals with very little care or just plain cruelly.
Source: Series / Animal Planet Heroes - Simon have "Downtown" Brown, a plain-clothes/undercover cop.
Source: Friend on the Force -
There was also the Colt Detective Special (1927-'86 and 1993-'95), a snub-nosednote Barrel shorter than three inches variant of the Police Positive Special which was popular among plain-clothes detectives, undercover cops and railway clerks.
Source: Cool Guns / Revolvers
Cite this Source
Undercover and Plain. (2016). Retrieved 2026, August 14, from https://thesaurus.plus/related/plain/undercover
Plain & Undercover. N.p., 2016. Web. 14 Aug. 2026. <https://thesaurus.plus/related/plain/undercover>.
Undercover or Plain. 2016. Accessed August 14, 2026. https://thesaurus.plus/related/plain/undercover.
Google Ngram Viewer shows how "plain" and "undercover" have occurred on timeline