noun
tracer
TRAY-suh
Tracer (noun) means a substance, such as a radioactive isotope or dye, used to track how something moves or changes through a system. Example: “Doctors injected a radioactive tracer to follow blood flow through the heart.”
noun
1
A substance, such as a radioactive isotope or dye, used to track how something moves or changes through a system.
"Doctors injected a radioactive tracer to follow blood flow through the heart."
2
A bullet or shell that leaves a visible trail of light so its path can be seen, especially at night.
"Tracer rounds lit up the night sky during the battle."
How to use tracer
Learner’s notesIn plain EnglishSomething used to track a path — either a marked substance followed through a body or system, or a glowing round of ammunition.
Common pairings
radioactive tracer
tracer bullet
tracer round
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Word forms
- Plural
- tracers
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Doctors injected a radioactive _____ to follow blood flow through the heart.
Etymology
Formed from trace and -er.
Synonyms
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tracer bullet
Rhymes for tracer
See all rhymes for tracer →Frequently asked questions
What does “tracer” mean?
The word “tracer” means a substance, such as a radioactive isotope or dye, used to track how something moves or changes through a system. In plain terms, something used to track a path — either a marked substance followed through a body or system, or a glowing round of ammunition.
How do you pronounce “tracer”?
“Tracer” is pronounced TRAY-suh (/ˈtɹeɪsɚ/ in IPA).
How do you use “tracer” in a sentence?
Here is “tracer” used in a sentence: “Doctors injected a radioactive tracer to follow blood flow through the heart.”
What part of speech is “tracer”?
“Tracer” is a noun.
How many meanings does “tracer” have?
“Tracer” has 2 distinct senses listed in this dictionary. The most common is: a substance, such as a radioactive isotope or dye, used to track how something moves or changes through a system.
