HMS Nonsuch was a Repeat Admiralty M-class destroyer that served in the Royal Navy during the First World War. The M class was an improvement on those of the preceding L class, capable of higher speed. Originally laid down as HMS Narcissus but renamed before being launched in 1915, Nonsuch joined the Twelfth Destroyer Flotilla of the Grand Fleet. During the Battle of Jutland in 1916, after being attacked by the light cruisers of the German High Seas Fleet, the warship rescued the damaged destroyer Acasta. The vessel formed part of the screen for the dreadnought battleships of the First Battle Squadron during the Second Battle of Heligoland Bight in 1917. In both actions, the destroyer reported no hits. After the Armistice that ended the war, Nonsuch was initially put in reserve and then sold in 1921 to be broken up.

The M class, more properly known as the Admiralty M class, were a class of 85 destroyers built for the Royal Navy of United Kingdom that saw service during World War I. All ships were built to an identical – Admiralty – design, hence the class name. 18 other vessels which were officially included within the 'M' class were built to variant designs by three specialist builders – 10 by Yarrow, 6 by Thornycroft, and 2 by Hawthorn Leslie; these are covered in other articles.