Parting shot
Meaning: A final remark, usually cutting or derogatory, made just before departing.
Origin: A 'parting shot' is now a metaphorical term but it clearly alludes to the shooting of weapons. The first such literal reference is in the writings of John McLeod, who was surgeon of His Majesty's Ship Alceste. McLeod includes this comment in A Narrative of a Voyage to the Yellow Sea, 1818:
The consort, firing a parting shot, bore up round the north end of the island, and escaped.
The figurative use of the phrase comes not much later, in the records of the Religious Society of Friends (The Quakers) - The Friend or, Advocate of Truth, 1828:
I think it would be much more becoming..., if you could separate without giving each other a parting shot. If you could but use this short sentence, "we cannot agree and therefore we separate."
That derivation of 'parting shot' appears to be very simple and straightforward. Not so fast; enter the Parthians and their 'Parthian shots'. The Partians were an ancient race who lived in north-east Persia. They were renowned archers and horsemen and were known for their practice of confusing the enemy by pretending to flee and firing arrows backwards while retreating - not the easiest thing to do on a galloping horse. The tactic must have been successful as in first century B.C. Parthia stretched from the Euphrates to the Indus River, covering most of what are now the regions of Iran, Iraq and Afghanistan. The Parthians' reputation was well known to English-speaking scholars in the 16th and 17th centuries. For example, Samuel Butler makes a specific reference to their battle tactic in An Heroical Epistle of Hudibras to His Lady, 1678:
You wound, like Parthians, while you fly, and kill with a retreating eye.
The use of the actual term 'Parthian shot' comes rather later. As with 'parting shot', the literal use comes first but both phrases mean virtually the same thing.
In Context: The reporter gave his parting shot to conclude the discussion.
Think About It: The last word in an argument is often described as a parting shot, a final blow or a sucker punch. Why would a verbal exchange be compared to these physical terms?