O5 or O-5 may refer to: * The "Outreach 5", emerging economies in the

Heiligendamm Process The Heiligendamm process is an initiative that will institutionalize high-level dialogue between the G8 and the five most important emerging economies, known as the O5 (Outreach 5): China, Mexico, India, Brazil and South Africa. The framework w ...

: China, Mexico, India, Brazil and South Africa * A symbol for the anti-Nazi

Austrian Resistance The Austrian resistance launched in response to the rise in fascism across Europe and, more specifically, to the Anschluss in 1938 and resulting occupation of Austria by Germany. An estimated 100,000 people were reported to have participated i ...

, where the 5 stands for E and OE is the abbreviation of Österreich * USS ''O-5'' (SS-66), a 1917 O-class submarine * HNLMS ''O 5'', a 1913 ''O 2'' class submarine of the Royal Netherlands Navy * SM ''UC-99'', a U-boat renamed O-5 for Japanese service from 1920 to 1921 *

Douglas World Cruiser The Douglas World Cruiser (DWC) was developed to meet a requirement from the United States Army Air Service for an aircraft suitable for an attempt at the first flight around the world. The Douglas Aircraft Company responded with a modified varia ...

, also designated as Douglas O-5 *

De Havilland Canada Dash 7 The de Havilland Canada DHC-7, popularly known as the Dash 7, is a turboprop-powered regional airliner with STOL, short take-off and landing (STOL) performance. It first flew in 1975 and remained in production until 1988 when the parent comp ...

, also designated as De Havilland Canada O-5 * A subclass of the

LNER Class O4 The London and North Eastern Railway (LNER) Class O4 initially consisted of the 131 ex-Great Central Railway (GCR) Class 8K 2-8-0 steam locomotives acquired on grouping in 1923. The engines were designed by John G. Robinson and built at the GCR' ...

, locomotive class * O-5, the

pay grade A pay grade is a unit in systems of monetary compensation for employment. It is commonly used in public service, both civil and military, but also for companies of the private sector. Pay grades facilitate the employment process by providing a fix ...

for the following officer ranks in the U.S. uniformed services: **

Lieutenant colonel Lieutenant colonel ( , ) is a rank of commissioned officers in the armies, most marine forces and some air forces of the world, above a major and below a colonel. Several police forces in the United States use the rank of lieutenant colone ...

in the Army, Marine Corps, Air Force, and Space Force **

Commander Commander (commonly abbreviated as Cmdr.) is a common naval officer rank. Commander is also used as a rank or title in other formal organizations, including several police forces. In several countries this naval rank is termed frigate captain. ...

in the Navy, Coast Guard, Public Health Service Commissioned Corps, and NOAA Commissioned Officer Corps *

Otoyol 5 ( en, Motorway 5), named the Gebze-Orhangazi-İzmir Motorway ( tr, Gebze-Orhangazi-İzmir Otoyolu) and abbreviated as O-5, is a toll motorway in Turkey. Since being completed in 2019, it connects the Istanbul metropolitan area with İzmir, via ...

, a toll motorway in Turkey * The

time-displaced X-Men The X-Men are a superhero team appearing in American comic books published by Marvel Comics, first appearing in ''The X-Men'' #1 by artist/co-plotter Jack Kirby and writer/editor Stan Lee in 1963. Although initially cancelled in 1970 due to lo ...

, also called "The Original 5" *The senior “overseer” position in the

SCP Foundation The SCP Foundation is a fictional secret organization documented by the collaborative-writing wiki project of the same name. Within the website's shared universe, the Foundation is responsible for capturing, containing, and studying various p ...

See also