Definitions

1. noun

a person or thing that traces or follows a track or trail

“The detective was a skilled tracer, able to follow the faint trail of evidence.”

2. noun

a device or signal used to locate or track something, especially a radio wave or a particle

“The scientists used a tracer to track the movement of the radioactive particles.”

3. verb

to follow or track something, especially a track or trail

“The hikers tried to tracer their route to find their way back to camp.”

4. verb

to add a substance to something, especially to track its movement or location

“The scientists tracers the water with a radioactive dye to track its flow.”