tracer

Từ điển WordNet v3.1 - WordNet Dictionary

noun

1. an investigator who is employed to find missing persons or missing goods
• Hypernyms:
detective, investigator, tec, police detective
2. an instrument used to make tracings
• Derivationally related forms:
trace
• Hypernyms:
instrument
3. (radiology) any radioactive isotope introduced into the body to study metabolism or other biological processes
• Topics:
radiology
• Hypernyms:
radioisotope
4. ammunition whose flight can be observed by a trail of smoke
• Syn:
tracer bullet
• Hypernyms:
ammunition, ammo