Tracer may refer to:

Science

Flow tracer A flow tracer is any fluid property used to track the flow velocity (i.e., flow magnitude and direction) and circulation patterns. Tracers can be chemical properties, such as radioactive material, or chemical compounds, physical properties, s ...

, any fluid property used to track fluid motion * Fluorescent tracer, a substance such as 2-NBDG containing a fluorophore that is used for tracking purposes * Histochemical tracer, a substance used for tracing purposes in histochemistry, the study of the composition of cells and tissues *

Isotopic tracer Isotopic labeling (or isotopic labelling) is a technique used to track the passage of an isotope (an atom with a detectable variation in neutron count) through chemical reaction, metabolic pathway, or a Cell (biology), biological cell. The reactant ...

, a substance with an isotope that has been enriched to a greater level than that found in nature *

Radioactive tracer A radioactive tracer, radiotracer, or radioactive label is a synthetic derivative of a natural compound in which one or more atoms have been replaced by a radionuclide (a radioactive atom). By virtue of its radioactive decay, it can be used to ...

, a substance containing a radioisotope that is used for tracking purposes * TRACER (cosmic ray detector) (Transition Radiation Array for Cosmic Energetic Radiation), a balloon-borne cosmic ray detector * Tracers, a colloquialism for visual trailing, often experienced in connection with drug use * TRACERS (

Tandem Reconnection and Cusp Electrodynamics Reconnaissance Satellites Tandem Reconnection and Cusp Electrodynamics Reconnaissance Satellites (TRACERS) is a planned orbiter mission tasked to study the origins of the solar wind and how it affects Earth. TRACERS was proposed by Craig Kletzing, Craig A. Kletzing at t ...

), a pair of orbiters to study the solar wind

Military

* Tracers,

tracer ammunition Tracer ammunition, or tracers, are bullets or cannon-caliber projectiles that are built with a small pyrotechnic charge in their base. When fired, the pyrotechnic composition is ignited by the burning powder and burns very brightly, making the p ...

, special bullets that burn brightly to enable the shooter to follow the bullets' trajectories * Tactical reconnaissance and counter-concealment-enabled radar (TRACER), a radar system developed by the United States Army *

Grumman E-1 Tracer The Grumman E-1 Tracer (WF prior to 1962) was the first purpose-built airborne early warning aircraft used by the United States Navy. It was a derivative of the Grumman C-1 Trader and entered service in 1960. It was replaced by the more mode ...

, a carrier-borne early warning aircraft used by the United States Navy in the 1960s *

Tactical Reconnaissance Armoured Combat Equipment Requirement The American Future Scout and Cavalry System (FSCS) and British Tactical Reconnaissance Armoured Combat Equipment Requirement (TRACER) were a joint U.S.–British reconnaissance vehicle program. The program was begun to replace the UK's Sabre (tan ...

, a joint British–American scout vehicle

Arts and entertainment

Music

* Tracer (band), an Australian rock band * ''Tracer'' (album), a 2012 album by Teengirl Fantasy * "Tracers", song by Ash (band) from '' A-Z, Vol.1'' 2010 * "Tracers", song by Miracle Fortress from ''

Was I the Wave? ''Was I the Wave?'' is the second studio album by Miracle Fortress, released on April 26, 2011. The album departs from the indie rock of '' Five Roses'', and is instead more of an electronic offering. As with ''Five Roses'', all songs were composed ...

'' 2011 * "Tracers", song by Trans-Siberian Orchestra from ''

Night Castle ''Night Castle'' is the fifth studio album by the Trans-Siberian Orchestra. It was released on October 28, 2009 as a double CD with a 60-page booklet illustrated by Greg Hildebrandt, and debuted at No. 5 on the Billboard charts and No. 1 on t ...

'' 2009

Films

* ''Tracer'' (film), a 2016 Vietnamese film * ''Tracers'' (film), a 2015 American film

Video games

* ''Tracer'' (game), a 1995 action-puzzle video game * ''Tracer'', a 1976 Sega arcade video game * Tracer, leader of the Eliminators in '' The Warriors'' * Tracer (''Overwatch''), a player character from the video games ''Overwatch'' and ''Heroes of the Storm'' * Tracer Tong, a character from the video game series ''

Deus Ex ''Deus Ex'' is a series of cyberpunk role-playing video games, set during the mid 21st century. Focusing on the conflict between secretive factions who wish to control the world by proxy, and the effects of transhumanistic attitudes and technol ...

Comics and comic strips

* Tracer (DC Comics), a DC Comics character * Tracer (Marvel Comics), a Marvel Comics supervillain * Tracer Bullet, one of Calvin's alter egos in ''Calvin and Hobbes''

Television

* ''Tracer'' (TV series), a 2022 South Korean television series

Transportation

Mercury Tracer The Mercury Tracer is a compact car that was marketed by Mercury from the 1987 to 1999 model years. The replacement for the Mercury Lynx, the Tracer was also sold as a three-door and five-door hatchback and a five-door station wagon; a four-doo ...

, an automobile * Tracer (bus), the bus system for Tracy, California * Yamaha Tracer 900 * Yamaha Tracer 700 * MonoTracer * Zerotracer * ''E-Tracer'' and ''X-Tracer'' by

Peraves Peraves AG was a Swiss manufacturer of high-end aerodynamically-enhanced cabin motorcycles. It won the Automotive X Prize for its entirely electric X-Tracer in 2010. By 2019 it had declared bankruptcy. History Peraves AG was founded in 1972 by S ...