Ranger

In general, a ranger is a keeper, guardian, or soldier that ranges over a region to protect the area or enforce law. See park ranger.

The mystique of the ranger has been harnessed for military, sports and governmental uses as well as appearing elsewhere in fiction. The Ranger program, for example, was a series of NASA unmanned space missions.

As used in J.R.R. Tolkien's fiction, a ranger is a guardian of the land who travels within the wilderness. This fictional motif was revisited by various fantasy roleplaying games.

See: Wiktionary - entry on 'ranger'.

Military

The Queen's York Rangers (1st American Regiment) (RCAC)
The Rocky Mountain Rangers
Canadian Rangers
US Army Ranger
Royal Irish Rangers
Irish Army Ranger Wing
Pakistan Rangers

Sports

Texas Rangers - Major League Baseball team
New York Rangers - American ice hockey team
Berwick Rangers - English-based Scottish League football team
Rangers - Scottish football team
Queens Park Rangers - English football team

Fictional Rangers

Aragorn - from J.R.R. Tolkien's The Lord of the Rings
Lone Ranger - fictional TV series
Walker, Texas Ranger
Role-Playing Game Ranger - Character class of Role-Playing Games like Dungeons & Dragons and Everquest (including Drizzt Do'Urden and the goddess Mielikki).
In the Babylon 5 universe, The Rangers are a class of warriors founded by the Minbari to eventually play a key role in the Shadow War.

Government

Science

The Ranger program of NASA unmanned space missions to the Moon.