E. Cobham Brewer 1810–1897. Dictionary of Phrase and Fable. 1898.
Cockshy (A).
A free fling or “shy” at something. The allusion is to the once popular Shrove-Tuesday sport of shying or casting stones or sticks at cocks. This sport is now superseded by pigeon-shooting, which is thought to be more aristocratic! but can hardly be deemed more humane.
