tracer

noun

trac·​er ˈtrā-sər How to pronounce tracer (audio)
1
: one that traces, tracks down, or searches out: such 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
2
: one who traces designs, patterns, or markings
3
: a device (such as a stylus) used in tracing
4
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 sense 1d

Examples of tracer in a Sentence

The enemy fired tracers at the aircraft carrier. They injected her with a radioactive tracer and tracked it via X-rays.
Recent Examples on the Web This new study showed that PET imaging, using a special tracer called 18F-fluoroestradiol (FES), can do just that. Sandra Rose Salathe, Flow Space, 25 June 2024 For the study, published in Scientific Reports, researchers scanned the brains of 54 healthy women aged 40-65 using PET imaging with a tracer that binds specifically to estrogen receptors. Sandra Rose Salathe, Flow Space, 25 June 2024 Smaller galaxies swarming around a larger one can be especially sensitive tracers of dark matter’s subtle effects, so cataloging and studying these satellites could be another way for researchers to learn more about how the invisible substance helped guide galactic formation and evolution. Phil Plait, Scientific American, 14 June 2024 Almeida admitted making trips to Mexico to get cash to buy bulk ammunition, including bullets with tracer capability. Beth Warren, The Courier-Journal, 12 June 2024 See all Example Sentences for tracer 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'tracer.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

14th century, in the meaning defined at sense 1

Time Traveler
The first known use of tracer was in the 14th century

Dictionary Entries Near tracer

Cite this Entry

“Tracer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tracer. Accessed 20 Jul. 2024.

Kids Definition

tracer

noun
trac·​er ˈtrā-sər How to pronounce tracer (audio)
1
a
: a person who traces missing persons or property
b
: an inquiry sent out in tracing a shipment lost in transit
2
a
: ammunition containing a chemical composition to mark the flight of projectiles by a trail of smoke or fire
b
: a substance and especially a labeled element or atom used to trace the course of a chemical or biological process

Medical Definition

tracer

noun
trac·​er ˈtrā-sər How to pronounce tracer (audio)
: 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

More from Merriam-Webster on tracer

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