Discussion Forum—A Way with Words, a fun radio show and podcast about language

Dictionary.com gibes two definitions for dick,  the one being a detective, and the other being an -anatomical reference, then says the word originated in 1545-1555,  Later on it suggests that the detective reference is 20th century,

They say "Meaning "detective" is recorded from 1908, perhaps as a shortened variant of detective."  It may not have been very popular.  Chester Gould originally called his character "Plainclothes Tracy" in 1931.  I've heard harness bulls called "Barney Fife", "Fearless Fosdick", and for that matter, called "dick". 

They also claim "The meaning "penis" is attested from 1891 in British army slang."  I wonder if Richard Johnson was a UKGBNI soldier.

But they omit any primary definition for 1550 to 1908.  Later on, they mention that it is short for Richard, and used to mean  "fellow, lad, man," (i,e, an ordinary joe) from 1553.

But none of this answered my question. To a pedant. does a detective mean a policeman, or does the term include private investigators as well?