plainclothesman[noun]Synonyms: detective, dick, eye, gumshoe, hawkshaw, investigator, Sherlock, Sherlock Holmes, sleuth, tec
[TahlilGaran] English Synonym Dictionary ▲
plain·clothes·man or
plain·clothes man (plān

klōz

mən, -klō
thz

-)
n.A member of a police force, especially a detective, who wears civilian clothes on duty.
[TahlilGaran] American Dictionary ▲