say it: in-VEH-stuh-gay-tur
investigator is a noun meaning "a scientist who devotes himself to doing research". It carries 3 recorded senses.
a scientist who devotes himself to doing research
a police officer who investigates crimes
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for investigator come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.