If the word "Cockney" appears in a cryptic clue, its most common purpose is to indicate H-dropping. On occasion it refers to other Cockney accent features like th-fronting.
Th-fronting according to Wikipedia technically means:
The use of the labiodental fricatives [f] and [v] for the dental fricatives [θ] and [ð]
Simply put, th-fronting is the pronunciation of "th" as "f" or "v". So "think" in Cockney speech becomes "fink", "brother" becomes "bruver".
This facet of speech is put to use in cryptic clues such as:
Times 24508: Release a trio of Cockneys? (4) FREE
THREE (trio) would sound like FREE (release) in Cockney accent.
As with H-dropping, other indicators of Cockney pronunciation are names of geographical areas where Cockney English could be spoken - East End, Bow, Albert Square, etc.
FT 13854 (Bradman): Nonconformist wise men from east of London may introduce themselves thus, we hear (3,4) WEE FREE
A member of the Free Church of Scotland is colloquially called Wee Free, which is how those from east of London may pronounce "we three" (wise men).
One for you to solve:
Independent 7869 (Dac): Plain and unsensational, as a Cockney might say? (2-6)
PS: Why actor Hrithik Roshan, who has no Cockney connections AFAIK, pronounces "th" as "f" is as yet an unsolved mystery.
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