How to open quickly – in a browser – a Wikipedia URL from Dictionary or from the 'Look Up in Dictionary' service dialogue?
In Dictionary.app at the foot of the page there's an option: 


View web page.


This is not the routine that I recall. 

Also the URL is not what's required – example: I want http://en.wikipedia.org/wiki/Parity_bit but Dictionary links to http://en.wikipedia.org/w/index.php?title=Parity_bit …