Since World War 2 the word "Blighty" is a term slowly declining in popularity used to refer to England. The term first came into existence during England's rule of India from the language of Urdu (which is now spoken mainly in Pakistan which has since separated from India). The original Urdu word is, "bilāyatī" or "vilayati," which translates to "foreign" or "European".
The word slowly evolved into a more common term during the World Wars. Instead of referring to someone as a foreigner or European, it slowly became the new nickname for England. During World War I, "Dear Old Blighty" was a common sentimental reference, suggesting a longing for home by soldiers in the trenches. Also used as an indicator of seriousness of injury, a "Blighty wound" meant that you were wounded so badly you had to be returned back home from duty.