The U.N. Spacy is a fictional military arm of the Earth U.N. Government (地球統合政府 chikyuu tougou seifu) from the Japanese anime series Macross. It was established (between years of 1999 A.D. - 2009 A.D.) by the successor to the modern United Nations in order to defend Earth from a possible attack by hostile aliens, and was involved in Space War I against an extra-terrestrial race called the Zentradi. Later operations of the U.N. Spacy expanded into interstellar colonization and general peacekeeping of off-world Earth settlements.
By the time of Macross Frontier (2059 A.D.), the U.N. Spacy had been reorganized into the "New U.N. Spacy" or N.U.N.S.
The term "spacy" (宇宙軍 uchuugun, lit. "space military" or "space army") is frequently considered to be a portmanteau of the terms army (陸軍 rikugun, lit. "land military" or "land army") and navy (海軍 kaigun, lit. "maritime military" or "maritime army"). In fact, this is not true. It originated in science fiction Anime in the early 1980s, when the animators were deliberately attempting to emphasize the realistic space-military aspects of their cartoons by deliberately copying the style and markings of American military vessels and vehicles. Most of these early animators had little or no understanding of english, and as many of the American military craft they were copying had markings that said "Army" and "Navy" it was an obvious mistake for them to assume a space force would be called a "Spacey." This was not considered a problem in Japan at the time, since these early shows were not intended for export, and frankly any English-looking signage would do, however it created something of an unfortunate pun when the shows were eventually viewed in the English-Speaking world. While some Japanese sources use the literal "Space Army" translation, the U.N. Spacy is probably best described as a kind of space-faring navy.
"Spacy" also appears in the Martian Successor Nadesico franchise, Voices of a Distant Star and Mobile Suit Gundam 0080: War in the Pocket OVAs (Original Video Animations). In the Gundam OVA it appears in the form of the "U.N.T. (United Nations Troops) Spacy" (連邦宇宙軍 renpou uchuugun) . In the context of Gundam, the term "Earth Federation Space Force" is now the official English translation for the Japanese 地球連邦宇宙軍 (chikyuu renpou uchuugun), and U.N.T Spacy has been retconned as the abbreviation for "Under Normal Tactical Special Assortment Construction Yard."