Seven ships of the British Royal Navy have been named HMS Indefatigable.

• The first Indefatigable was a 64-gun two-decked ship of the line (eventually razeed to a frigate) launched in 1784.

• The second Indefatigable was an armed ship purchased in 1804 and sold in 1805.

• The third Indefatigable was to be a 50-gun fourth-rate (2,084 tons, 176 ft long, 53 ft beam), carrying all 32-pounder guns. The ship was ordered from Woolwich 29 November 1832 but cancelled in March 1834.

• The fourth Indefatigable was also a 50-gun fourth-rate, launched in 1848, on load as a training ship after 1865, and sold 1914.

• The fifth Indefatigable was a 2nd class cruiser launched in 1891, renamed Melpomene in 1910, and sold in 1913.

• The sixth Indefatigable was a battlecruiser launched in 1909. She fought under Capt. C.F. Sowerby in the Battle of Jutland (1916), when a hit (probably from German Battlecruiser Von der Tann) penetrated the armour of her forward turret, leading to an explosion of the magazine and the sinking of the ship. All but four of her crew died.

• The Phaeton was renamed Indefatigable and used as a training ship from 1914.

• The seventh Indefatigable (R10) was an Implacable-class aircraft carrier. She took part in the hunt for German Battleship Tirpitz, and was later transferred to the Pacific theater, where she was the first British ship to suffer a Kamikaze attack. Due to the armoured flight deck typical for British carriers, she was not seriously damaged. After the end of World War 2, she was paid off, but later recommissioned as a training ship. She was finally scrapped in 1956.