Simple Definition of tracer
: 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
1 : one that traces, tracks down, or searches out: asa : a person who traces missing persons or property and especially goods lost in transitb : an inquiry sent out in tracing a shipment lost in transit
2 : one who traces designs, patterns, or markings
3 : a device (as a stylus) used in tracing
4a : ammunition containing a chemical composition to mark the flight of projectiles by a trail of smoke or lightb : a substance used to trace the course of a chemical or biological process; especially : label 3d
Examples of tracer
The enemy fired tracers at the aircraft carrier.
They injected her with a radioactive tracer and tracked it via X-rays.
First Known Use of tracer
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
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