noun \ˈtrā-sər\

: a type of bullet that shows its path by creating smoke or light as it moves through the air

medical : a substance that is put in a patient's body so that doctors can watch a biological process (such as digestion) or see how a condition (such as cancer) is progressing

Full Definition of TRACER

:  one that traces, tracks down, or searches out: as
a :  a person who traces missing persons or property and especially goods lost in transit
b :  an inquiry sent out in tracing a shipment lost in transit
:  one who traces designs, patterns, or markings
:  a device (as a stylus) used in tracing
a :  ammunition containing a chemical composition to mark the flight of projectiles by a trail of smoke or light
b :  a substance used to trace the course of a chemical or biological process; especially :  label 3d

Examples of TRACER

  1. The enemy fired tracers at the aircraft carrier.
  2. They injected her with a radioactive tracer and tracked it via X-rays.

First Known Use of TRACER

14th century

Rhymes with TRACER


noun \ˈtrā-sər\   (Medical Dictionary)

Medical Definition of TRACER

: a substance used to trace the course of a process; specifically : a labeled element or atom that can be traced throughout chemical or biological processes by its radioactivity or its unusual isotopic mass


Next Word in the Dictionary: tracer bullet
Previous Word in the Dictionary: trace of precipitation
All Words Near: tracer

Seen & Heard

What made you want to look up tracer? Please tell us where you read or heard it (including the quote, if possible).