The term 'DETECTIVE' is often used in slang to refer to a person who investigates crimes. The most common slang terms for DETECTIVE are 'FLATFOOT' (8 letters), 'GUMSHOE' (7 letters), 'DICK' (4 letters) and 'SHAMUS' (6 letters). FLATFOOT is an old-fashioned term that refers to a police officer or DETECTIVE, while GUMSHOE is a more modern term that implies someone who is stealthy and sly. DICK is a shortened version of the word DETECTIVE, and SHAMUS is an Irish-American term for a DETECTIVE.