is a slang
term of British
origin whose meaning has evolved over time. Partridge
in the third edition of his A Dictionary of Slang and Unconventional English
in 1949 recorded the term as "low" slang for penis
, "since ca. 1917". The term remains in recent use with that meaning.
By 1966, the term had also acquired the meaning of a man who let his girlfriend sleep with his male friends, and in the 1980s had a new meaning of a stupid or inept person. This meaning gained very wide circulation through its frequent use in Only Fools and Horses, and has entered common usage.