tracer

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noun trac·er \ˈtrā-sər\

Definition of tracer

  1. 1 :  one that traces, tracks down, or searches out: such 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. 2 :  one who traces designs, patterns, or markings

  3. 3 :  a device (such as a stylus) used in tracing

  4. 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 in a Sentence

  1. The enemy fired tracers at the aircraft carrier.

  2. They injected her with a radioactive tracer and tracked it via X-rays.

Recent Examples of tracer from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'tracer.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of tracer

14th century


TRACER Defined for English Language Learners

tracer

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noun

Definition of tracer for English Language Learners

  • : 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


Medical Dictionary

tracer

play
noun trac·er \ˈtrā-sər\

Medical Definition of tracer

  1. :  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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