- tracer - an investigator who is employed to find missing persons or missing goods
--1 is a kind of detective, investigator, tec, police detective
- tracer - an instrument used to make tracings
--2 is a kind of instrument
Derived forms: verb trace7, verb trace2 - tracer - (radiology) any radioactive isotope introduced into the body to study metabolism or other biological processes
--3 is a kind of radioisotope
- tracer, tracer bullet - ammunition whose flight can be observed by a trail of smoke
--4 is a kind of ammunition, ammo
- tracer - an instrument used to make tracings