Her Majesty's New Zealand Ship (HMNZS) is the designation of any New Zealand warship, as well as major New Zealand naval shore facilities.

It derives from "Her Majesty's Ship

Her Majesty's Ship

Her or His Majesty's Ship is the ship prefix used for ships of the navy in some monarchies, either formally or informally.-HMS:* In the British Royal Navy, it refers to the king or queen of the United Kingdom as appropriate at the time...

" (HMS) used in the United Kingdom

United Kingdom

The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

. The British monarch is also equally and separately the New Zealand head of state

Monarchy in New Zealand

The monarchy of New Zealand also referred to as The Crown in Right of New Zealand, Her Majesty in Right of New Zealand, or The Queen in Right of New Zealand is the constitutional system of government in which a hereditary monarch is the sovereign and head of state of the Realm of New Zealand,...

. Should the Queen be replaced by a King, the designation also changes to "His" rather than "Her" Majesty. Ships bearing this designation are the responsibility of the Royal New Zealand Navy

Royal New Zealand Navy

The Royal New Zealand Navy is the maritime arm of the New Zealand Defence Force...

. On 1 October 1941 King George VI

George VI of the United Kingdom

George VI was King of the United Kingdom and the Dominions of the British Commonwealth from 11 December 1936 until his death...

fixed his signature to the approval for the Royal New Zealand Navy and from that date all ships officially received the designation.