investigator vs tracer

investigator and tracer both are nouns.

Word	Noun	Adjective	Verb	Adverb
investigator	Yes	No	No	No
tracer	Yes	No	No	No

As nouns, tracer is a hyponym of investigator; that is, tracer is a word with a more specific, narrower meaning than investigator:

investigator: a police officer who investigates crimes
tracer: an investigator who is employed to find missing persons or missing goods

Other hyponyms of investigator include dick, gumshoe, hawkshaw, plainclothesman.

investigator (noun)	tracer (noun)
someone who investigates	ammunition whose flight can be observed by a trail of smoke
a scientist who devotes himself to doing research	(radiology) any radioactive isotope introduced into the body to study metabolism or other biological processes
a police officer who investigates crimes	an instrument used to make tracings
	an investigator who is employed to find missing persons or missing goods